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Causes, Solutions & Suggestions
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Scroll down to browse
through some archived SWIMMING POOL questions and answers.
Please access the Pool Topics Page and other links, at the top of
every page, for additional information.
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Staining
is a detraction from the overall appearance or aesthetics of the pool, as well
as an annoyance. Colored stained walls, floors, steps and other underwater
surfaces can result from the untreated presence of heavy metals, such as
iron, manganese and copper, in the pool water. These metals can
occur naturally in water (especially well water) or may have been introduced
into the pool water, as a result of corrosion. Copper algaecides are
usually in a chelated or stabilized form and are not normally a problem, when
used properly as directed. Pool stain removal can be accomplished with the
proper materials and techniques. New or freshly resurfaced masonry pools
can be more susceptible to staining, until the underwater surfaces have "cured"
and come to equilibrium with the pool water. Stain avoidance treatment should
be considered, whenever a water analysis indicates the potential for a problem.
If possible, test the source water before it is added to the pool, as it is best
to add mineral treatments prior to the addition of oxidizers (chlorine, bromine
or shock) or the pH and/or total
alkalinity are increased.
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►
Purple Pool
Walls?
Gunite pool, pink algae year ago, used algaecide
to get rid of it, and it worked, until it got warm. Then blue-purple color was
on the walls, step walls (not on the bottom) of the pool. When got cold,
went away. Now with it warmer, it's back. Water
testing shows Calcium 600 (that is after 2 1/2 pool drains) chlorine is high,
rest ok. Minerals - no iron. Pool
people thought needs to be washed. Lowered water 1/2 way, and used
liquid chlorine on the steps. What ever the chlorine touched that was
purple TURNED BLACK! The towel I used to put the chlorine on turned
warm. It did come off when brushed & some elbow grease. Questions: what is going on, besides a chemical reaction of some type? Should
a chlorine wash get rid of this? We
are selling the house and need to have it fixed for new buyer. Thank
you.
Susan R., 5/2/2003
THIS IS
DEFINITELY NOT AN ALGAE PROBLEM! IT IS DEFINITELY A MINERAL PROBLEM!
The action of the chlorine turning the color from purplish to black is
indicative of an oxidizing chemical reaction. A chlorine "wash" or shock
treatment will probably be a waste of time and money. Purple pool water
and stains can
be indicative of manganese. It is not a common problem and most dealers do
not test for it. If your water came from a private well, there is a
greater likelihood that manganese could be involved. Another more likely
possibility is copper. Copper in the presence of high levels of calcium
hardness, which you do have, can cause dark or black stains, under certain
conditions. The blue-purple color could have been a faint deposit of
copper, normally bluish in color, and the background color of the pool
finish. When the pool people suggested a "wash", I suspect that
they were referring to an acid wash. This type of treatment is
periodically done on masonry pools to remove surface deposits and restore the
look of the pool finish. It may be possible to remove the stains by
chemical treatment. Try this. Put 1/2 pound of pH reducer powder in
a white sock, shut off the filter and drop onto a stained area. Check
after 15-30 minutes. If improvement is seen, this would be indicative that
chemical treatment might work. Chemical treatment will require that you
add 2-3 doses of a quality mineral treatment, to help prevent further
discoloration. Raise the water level above all of the discoloration and
staining.
Add muriatic acid until the pH has dropped to below 6.0. It may take
considerable acid, depending upon the starting pH and the total
alkalinity.
Without the lowering of the pH, you are not likely to
remove the stains. Some pool stores sell oxalic acid. This can help
in removing the stains and can be added to the acidic pool. This
material will react will chlorine, so add only when the chlorine level is very
low.
At that point the addition will zero out the chlorine and create conditions more
favorable for pool stain removal. Use the brush to help things along.
Metal parts in the pool, pump and filter may be affected by the acidic
conditions. Clean or bypass the filter, if possible, to remove stain
causing debris from the filter. Depending upon the pH, you should see
improvement in a day or so. Once the stains are removed, add another 2-3
doses of a quality mineral treatment, before restoring the pH. It will be
necessary to shock the pool, in order to destroy all of the oxalic acid and
reestablish proper pool chemistry. Where did the copper come from?
If you have a heater you may have subjected it to corrosion. Copper
algaecide is another possibility. Refer to other related topics in the
archives. I hope it works out for you.
Sincerely.
Alan Schuster, 5/2/2003
Thank you Alan. Yours has
been the first sensible response I have had. It does come off with the
sock & sodium bisulfate. Took no brushing. We cannot bypass our
filter. Can we lower the pH, then bring it back up and still have swimable
water? Thank you again.
Susan R., 5/2/2003
The purpose of
the bypass was to minimize corrosion. Clean the filter out before
treatment and again afterwards, so as not to redissolve what you are trying to
remove from the pool walls. Don't neglect to add the mineral treatment!
Otherwise, you could get a recurrence. You can swim as soon as you restore
the pH and the chlorine levels. Inasmuch as the stain was removed without
the oxalic acid, I don't see the need to add the product. It seems that
things will work out for you. Good luck with the sale of the house.
Sincerely.
Alan Schuster. 5/2/2003
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►
Huge Black
Stains?
Alan, I just decided to open my
pool for the summer. Unfortunately I do not have a lot of time to care
for it myself so it sat all winter without a cover. I live in Ft Worth TX
so temperatures stay pretty warm most of the year. I have huge oak and
maple trees in my back yard and their leaves fell in the pool and decomposed.
I had a service empty the pool and acid washed it but they are TONS of huge
black stains at the bottom of my pool. I have a 30,000 gallon gunite and
plaster pool and the plaster is wearing off. The pool is at least 15 years
old, and I have lived here for 3 years. Is there something that can
remove these stains or should I just re-plaster the pool? I think I am
getting a fair deal on the replastering, so I am considering it. Thanks
Randall, Ft.
Worth, TX, 6/5/2004
It does appear that you will be refinishing the pool sooner rather than later.
There 's
little sense investing a lot of time and money, but it still might be a good
idea to clean up the pool. It might make for a better plastering job? Most likely
the pool discoloration and stains are the results of tannins from all of the
leaves, especially the oak leaves. Boost the Free Chlorine level to 5-10
PPM and keep it there for a day or so or until the stains disappear.
Adjust the water chemistry as necessary and keep the filter operating.
This should be the trick and you'll be in a better position to determine when to
resurface the pool. The new finishes today can be quite different
from the one used in your pool. It is not just plain old plaster any more.
There are all types of
aggregate finishes with different
looks and properties to consider. The finishes from Pyramid Cement
Products are more durable and less affected by chemicals:
www.pyramidcement.com Good luck and I hope that I've been
helpful.
Sincerely.
Alan Schuster, 6/5/2004
►
Waterline Stain?
We have an inground liner pool
that is only 3 years old. There is an ugly ring around the pool at the water
line. This past holiday weekend, we scrubbed and chemicalized the area, trying
to remove it. We tried cleaners, ascorbic acid, stain removers and metal out.
Nothing helped. At this point, we have rubbed off the tile pattern in some
places. Is there a way to just replace the water line area? Your website has
been helpful in the past and we hoping that you can suggest something or know of
something. Thank you.
Barbara, 7/6/2004
At this
point, it is doubtful that any type of chemical cleaning will solve the problem.
There is a product that will allow you to apply a new border, right over the problem area.
It sounds like just what you're looking for.
To access product
and ordering information on BorderLines, click here
Good luck and I hope that it works out for you.
Sincerely. Alan
Schuster, 7/7/2004
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►
Fertilizer Stains?
We recently fertilized our
yard, and accidentally got some in our inground pool. The rust stains are
scattered throughout the pool. We called our pool company, and they suggested
adding ascorbic acid, which we did, but to no avail. Is there anything else we
can do to fix this problem?
Jon G., 4/2/2004
The pool stains that resulted are due to iron and other trace minerals, that
are present in the fertilizer.
If you
simply added the ascorbic acid to the pool, it is unlikely that anything
beneficial will result.
The chlorine could have destroyed the ascorbic acid, before it contacted the
stains. Try this. Add 1/2 pound of pH reducer powder to a white sock, shut
off the filter and drop onto a stain. Position using the vacuum pole and
leave in place for 5-10 minutes. Move the sock around with the vacuum pole
after this period. If the stain is gone, repeat elsewhere, as needed. Once
the stains are gone, add a dose of metal treatment, in order to avoid a
recurrence. I hope that this information proves helpful.
Sincerely. Alan
Schuster, 4/2/2004
►
Vitamin C Treatment?
Hi Alan, I searched your site for references to
treating stains with vitamin C and couldn't find anything. I have an inground
fiberglass pool that came with a house I purchase several months ago. The pool
began getting stains and with help from my local pool water testing company
tried unsuccessfully to get them out. I tried algaecides, etc, and metal stain
removers and nothing worked. My water tested negative for iron and copper.
Someone mentioned to me to use vitamin C and I noticed the original pool/house
owner had bottles of vitamin C stored away and I said well maybe he used that -
which made no sense to me. I tried it and bam, the stains vanished almost
immediately. What in the world? Can you help me understand this?
What were
the stains and why would vitamin C of all things work? Thanks!
Sonny M., Wake Forest, NC,
6/4/2004
There are many
references to vitamin C on the Pool Staining Problems Page. Vitamin C is
ascorbic acid and there are many references to that as well.
If the problem is a metal
stain, adding algaecide or shock is useless. Adding a metal treatment, without
creating acidic conditions, rarely works.
The vitamin C tablets worked because it is an acidic, reducing
(antioxidant) agent and you were able to put it right on the stain. Ascorbic or
oxalic acids are available, in many pool stores, for use in treating stubborn
metal stains. If an entire pool needs to be treated, all of the chlorine should
be discharged, the pH lowered to about 6.0 and then the ascorbic or oxalic acids
are added. The important thing is that it worked.
Enjoy the season.
Sincerely. Alan Schuster,
6/5/2004
► Working Stain Removal
Scenario?
A Staining question for you. We have
an inground 45,000 litre pool with a vinyl liner. We have been getting
a yellow/gray discolouration on the vinyl liner (bottom and sides). We
thought it was algae but chlorine seemed to have no effect. I then
tried pH reducer in a sock and after about 30 minutes, about a 4' diameter
area in the deep end (where I laid the sock in) was nice and bright
again. I approached my pool store with the results to get an idea on the
best thing to use to reduce the pH to clean the entire liner, as well as
what to add to ensure the mineral or metal doesn't precipitate back out.
They were a bit suspicious about the results and were very concerned with
the liner being damaged with a lower pH. What do you think of this?
What is the best method for lowering the pH - pH reducer or Muriatic
Acid? Do I need to neutralize the Chlorine prior to lowering the pH?
After reading all of the posted info on your site I think this is the
method.
1) Neutralize the Chlorine
2) Lower the pH to eliminate the stain
3) Add metal reducer type product to help treat the minerals/metals
4) Raise the pH to appropriate levels
5) Raise the Chlorine
6) Adjust the balance of the chemicals
7) Add a metal reducer product periodically
Is this the right methodology? A bit long winded to ask whether the
lower pH will damage the liner but I thought I'd give as much info as
available. Thanks.
Your
scenario should work. Using ascorbic acid makes it better and faster,
but the chlorine must be eliminated. Concern about the liner is a
consideration and that is why you don't want to go below pH 6.0 or prolong
the treatment time. It doesn't matter if you use muriatic acid or pH
reducer. Muriatic is more concentrated and usually less expensive. pH 6.0
is what counts - not how you get there. The stains are
probably due to iron, copper and other trace minerals and are rarely removed
by simply adding a metal treatment. Try this. Place a few vitamin C
(ascorbic acid) tablets on a stain, shut off the filter and leave in place
for 15 minutes. If this worked, it is likely that treating with oxalic or
ascorbic acid will work. Put 1/2 pound in a white sock and drop onto a
stain. Slowly move around with a vacuum pole. Repeat elsewhere, as
necessary. Some pool dealers carry these products. Have the pool
and source water tested for iron and copper. ADD A DOSE OF A QUALITY METAL
TREATMENT FOR EVERY 0.5 PPM OF IRON OR COPPER. At the very least add two
doses. If the stained area is too broad to be treated with the "sock", you
may have to lower the pH of the pool to 6.0, discharge all of the
chlorine and add a few pounds of the oxalic or ascorbic acids.
Thereafter, add a dose of metal treatment monthly or prior to adding new
water, in order to avoid minimize the possibility of a recurrence.
I hope that I have been
helpful.
Sincerely. Alan Schuster, 5/2/2007
►
The Blues?
Just want to get a head start on this years pool
season. Last July our Alkalinity. was low so we were told by our local pool
store to put alkalinity plus into our inground pool (32000 gallons give or
take). Within 24 hours we had a blue stain throughout the pools liner. on the
walls and steps etc. It even stained our son's scalp blue. Our pool store, that
sold us the alkalinity plus said this is common when you raise the alkalinity
(used 50lbs) as much as we had to. I put a ton of stain remover in the water and
it cleared up around August. Is this blue stain common when you raise the TA in
a pool? Wondering,
1/18/2006
Such a thing will only happen, if there is copper present. It seems likely
that your pH and TA were low for an extended period of time and that you have a
heater. This corrosive chemistry caused some copper to dissolve from you
heater or copper pipes. When you raised the pH and/or TA, it precipitated.
You would have been better off adding a metal treatment first. From now on
I would add a dose of a metal treatment monthly and avoid low pH conditions.
Proper TA is part of that. If you use trichlor in a feeder, it must be last
in line and separated from the heater by a check valve. Otherwise,
corrosive solutions can backup into the heater, after the pump is shut off.
I hope that this information will help you understand what transpired.
Sincerely. Alan Schuster,
1/19/2006
►
An Ionization/Staining Conundrum?
Great site! I have a 25000 gal gunite
pool that is two years old. The previous owners used chlorine and last year I
switched to an ionizer/oxidizer. Toward the end of the summer I started to get
brown-black staining of the bottom. I have a problem with the pH constantly
creeping up. What is the best way to remove the mineral stains and use the
ionizer/oxidizer? How long should I use the oxidizer every day? One turn of
the filter is 4 hours. Thanks.
Dr. Ed S., 3/8/2005
The stains could be the result of
iron, manganese or other heavy metals that might have been present in the source
water. You should test both the pool and source water for heavy metals. The
sanitizing system that you are using seems to be one that utilizes copper ions
and oxidation. Too high a copper level, especially in the presence of high
calcium hardness and high pH, can cause dark staining. Testing the pool
for copper can determine if the level is too high.
Dealing with the copper, iron or manganese or
staining could require metal treatments and that could temporarily eliminate or limit the algaecidal function of the
copper.
In this case, you must treat the stains and for a period of a least a few
months, shut off the ionizer or pay close attention to the copper level.
To maintain algaecidal activity, I suggest that you use a polymer based
algaecide for this period of time. To remove the stains, try this.
Put 1/2 pound of pH reducer in a white sock and drop onto a stained area.
Shut off the filter and leave in place for about 1/2 hour. If this works,
you can probably remove the stains by lowering the pH to about 6.0. The
oxidizer that you are using does tend to raise the pH. If it doesn't work
repeat with ascorbic acid. If that works, you will have to lower the pH
and keep the oxidizer off for 24 hours. Once the stains are removed, add a
double dose of a quality metal treatment. Resume oxidation after 6-8
hours. The addition of this product will negate the copper ions and
require you to use the polymer algaecide. I believe that you are better
off operating the oxidizer for periods spread throughout the day. The
active oxygen is not long lasting and you should get better results with 3 or 4,
2-3 hour oxidizing sessions, spaced throughout the day. If the timer
doesn't allow for this, run it during the daylight hours. Some filters can
help remove oxidized heavy metals: diatomaceous earth filters or zeolite
filled sand filters, in particular, are especially effective. I hope that
this information proves helpful.
Sincerely. Alan Schuster,
3/8/2005
►
Covering Waterline Stain?
Our vinyl liner that is only four years old. For
the most part it is in great shape and we are not ready to replace it. Is there
any type of stick on border that we can put around the top to hide the
faded/stained imprint? Or is their a paint or magic marker that we
could use to repair the faded portion of the border?
Bashful, 5/11/2005
I have never heard of a paint
that could be used or of any type of marker. However,
there is an adhesive border that could be used to create a new waterline.
For product
and ordering information on BorderLines, click here. I hope
that this will work out for you and that this website has been helpful.
Sincerely. Alan Schuster,
5/12/2005
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►
Reverse Side Stain?
Alan: I have a medium size stain in the deep end
of my pool. It is dark looking and appears only to be in one spot. I had a new
liner installed two years ago. The local dealer said it was a problem that
sometimes arises under liners, because the government banned a certain treatment
that companies were using on the liners before installation. I have a
20x40 pool and use chlorine. The locals said to try a chlorine tablet
inside panty hose and let it set on the spot up to one minute. This did not
work. Now they tell me to treat the surrounding soil with ferrous (iron) sulfate
to change the soils pH. The pool tech said this was a new treatment and
has worked on some stains. Have you heard of this and do you think this
might work? These are reputable businesses and I have done business with
them since buying this property ten years ago. Please advise? I live in Decatur
Alabama. Thank you,
Daryl G., Decatur, AL, 1/25/2005
I have heard of this treatment.
I believe that the premise is based on treatments used in landfills.
Ferrous (iron) sulfate is added to the ground around the perimeter of the pool.
If it works, it is not because it is acidic. If that were the case, there
are better acids to add. Ferrous sulfate is a reducing agent, that will
react with oxygen containing products. The theory is that it creates an
oxygen reduced zone, as it diffuses under the pool. The stains are
probably being caused by the growth of certain molds or fungi.
Treatment with the chlorine tablet in the panty
hose, will only serve to bleach the liner. It will not work on a problem
that exists on the reverse side of the liner.
You have nothing to lose by trying this ferrous sulfate treatment. Make
sure that none of the chemical gets into the pool water or else staining and
discoloration will result. Please let me know how it turns out, as I will
share this information with others. I have no information on any recently
banned treatment. Good luck and I hope that I have been of some help.
Sincerely. Alan Schuster,
1/25/2005
►
Using Ascorbic Or Oxalic Acid?
I have tested
the two options that you have recommended and the one that works best is the
Vitamin C. It works very smoothly, no damage to the finish and cleans almost
completely the stains Only a little shade remains, but it's not very noticeable. Now I
suppose I would have to move to the acid for the other stains. Which one
should I use, oxalic or ascorbic acids, and how do I apply it? Are they
expensive? Would another option be to continue using the vitamin C?
Once again your help is highly appreciated. Before I got your advice, I
tested unsuccessfully a test kit for stains and a treatment product, which
didn't work and eroded the finish. Have a great holiday season. Best
regards.
Gustavo B., 12/21/2004
PS All my
friends and my pool service guy already know about your site!
Your already know that ascorbic acid will work, so it is the product that I
would recommend. It is not inexpensive, but is by no means prohibitively
costly. If it works, it is less expensive than products that don't perform
satisfactorily! To help get the best effect, allow the chlorine level to
drop to near zero. If you are dealing with limited areas, as is the usual
case with fertilizer stains or a foreign object, put some in a sock and drop onto the stained area.
Slowly move around with a pole. To treat the entire pool, broadcast the
product over the surface. If the filter is off, it may reach the bottom,
in greater strength. It won't damage pool finishes. Start the filter
running, after about 1/2 hour. Once the stains are gone, add a dose of a
metal treatment and wait several hours before restoring the chlorine and pH
levels. Enjoy the holidays - stain free hopefully.
Sincerely. Alan Schuster, 12/21/2004
►
Using Ascorbic Acid?
First off, great site. You have been the only
person that has steered me in the right direction. My wife and I bought a house
last year and opened the pool for the first time (2003). The pH level was
unreadable (very low). After about 1.5-2 weeks we were able to get it to
7.2 (don't even ask me what the previous owner did). Mid pool season last year
we noticed some purple and tan staining. We spoke to pool places, but they
were no help. This year we were told it may be metal, so we tried a metal
out product. Nothing. Then we finally got directed to your web page from a pool
message board. This evening I took a Vitamin C tablet, and sure enough, I was
practically able to draw in the stain. The bright blue liner popped right
through. So now that I know I have to get some ascorbic acid, drop Cl and pH way
down, I have a question. Since the vitamin C took it right off without messing
with the Cl or pH, why couldn't I put some ascorbic acid in a sock the way the
chemical level is now and scrub the stains, then add a metal remover?
Would the stains be harder to remove? Or would the stains I am removing
float through the water and stain other areas? Again, thanks for your
website, my wife and I are so anxious that we may now be able to have a nice
looking liner.
Greg O., 6/10/2004
You could put
ascorbic acid in a sock and run it across the bottom. The problem is that
chlorine will destroy ascorbic acid and that is why I suggest dropping the
chlorine level to zero. The vitamin C tablet is useful to determine if the
treatment, will work. If the whole bottom and/or walls are stained, the sock
trick may prove difficult. I would lower the pH to about 6.5, discharge all the
chlorine by adding chlorine neutralizer and then follow with ascorbic acid,
using the label dosage recommendations. If you can't find ascorbic acid, you
could try using oxalic acid. Once the stains are removed, add a double-triple
dose of a quality metal treatment. This is important to help avoid a
recurrence. Have your tap water tested. If iron is present, add a dose of
metal treatment monthly and prior to any new water being added. I'm glad the you
found the website. Enjoy the season.
Sincerely.
Alan Schuster, 6/10/2004
► Ascorbic Acid
Effect On Chlorine?
My pH at this point is only
slightly low. What I'm concerned about now is I used the pool today and
tested after use and there is a VERY low chlorine level. How can that be?
I just shocked the pool 2 days ago. I just put 2 tablets in the skimmer
and am letting the pool run now. The water is clear and blue. (I also have a
large delta UV light connected to this pool.). But I'm just shocked that
the chlorine level went down so fast. Maybe consuming all the algae really
depleted the chlorine? Or, do you think my using the ascorbic acid used
for the step stains effected the chlorine level?
Pat T., 4/10/2007
Ascorbic Acid
reacts with chlorine. That is why you want the chlorine level low to before
addition. After the stains are removed and metal treatment has been
added, you must keep adding chlorine, until a stable 1-3 PPM level is
established. Enough fast dissolving chlorine has to be added to destroy both
the residual ascorbic acid and any remnants of algae or organic waste.
Once down, it should be easier to maintain. I hope the information is
helpful.
Sincerely.
Alan Schuster, 4/11/2007
►
Yellowish-Brown
Stain? Alan, I
came across your website from the
Aquatics International
magazine. I have had a staining problem for a couple of years that
maybe you can answer. I operate two indoor, commercial pools. One is a 110,000
gallon recreational pool, the other is a 300,000 gallon competitive pool. The
recreational pool has a yellowish-brown stain on the bottom of it. I have tried
scrubbing with metal brushes and other tools with no luck. Last year we drained
the pool completely and acid washed the bottom which did get rid of the stains
but they have come back. We use calcium hypochlorite for sanitation and
muriatic acid to lower pH. We keep the temperature in the recreational pool at
85-87 degrees and the temperature in the competitive pool at 80 degrees. For
some reason I do not have a problem with staining in the competitive pool. I
have never checked for levels of iron or copper. Do you know what is
causing this stain? Thank you for any input.
Kevin B., 1/18/2005
It is
difficult explain why only one pool is experiencing this problem, especially if
the chemicals are the same and the materials of construction are similar.
The only thing that comes to mind is that they were filled at different times -
one after the other - and this introduced sediments, that were lifted off the
bottom of the pipes.
Your
description and the fact that the stains are removed with acid washing, suggests
the problem is metals.
Iron
would be the most likely. Copper can produce blue stains and, in the
presence of high calcium hardness levels, can produce dark stains.
Manganese can be present in some well water and produces dark stains. I
suggest that you have the pool water and source water tested for iron, copper
and manganese. For information on performing these tests go to:
www.lamotte.com
Metals problems can be avoided by the
prior treatment of the pool with appropriate chelating agents. Even if no
metals are detected, I would add a dose of a metal treatment now and additional
product prior to adding new water. I hope that this information helps to
explain the mystery.
Sincerely.
Alan Schuster, 1/19/2005
►
Tannin Stains:
Maybe Yes - Maybe No?
Hey Alan. Far and away,
yours is the best site I have seen on stain removal. I have looked through all
of the suggestions and I am hoping you will clarify a couple of things for me.
I have reddish-brown stains that are all in the area of where leaves deposited
themselves, so I am 90% sure they are stains of the tannin variety. I have
read where you suggested a chlorine ratio of 5 ppm to get rid of the stains.
The thing is that I have a salt chlorinator for my gunite / plaster pool that
keeps the level pretty steady between 4 and 5 parts per million depending on the
temperature. I have no algae problems, the water is crystal clear, and all
chlorine is free. The problem is that the stains aren't even close to
disappearing. My pH has been difficult to steady, but has been about 7.4
for the last week. The local pool specialist suggested that I use ascorbic acid
to remove the stains, but that seems contrary to your advice. In fact, the
pool specialist explained that I had to drop my Chlorine level in order for the
ascorbic acid to be effective. Metal and mineral tests proved negative.
Should I try the pH down in the sock trick or shock the pool with tablets to
increase my chlorine level? Thanks.
Tony D, 2/23/2005
The evidence
does point towards tannins, but the elevated free chlorine should have done the
job. The only explanation would be poor circulation, such as if there was
no main drain. Do you have a
pool cleaner?
Use it to improve the bottom circulation! Try sprinkling some trichlor granules on the
stains and leave overnight. If this doesn't work, the problem is not
tannins! A metal stain becomes the most likely cause of the problem.
By all means try the pH reducer in a sock. If it doesn't work, try placing
a few vitamin C tablets on a stain. If that works, then the use of
ascorbic acid should be the next step. You will have to lower the pH and
zero out the chlorine level, in order to prevent the chlorine from destroying
the ascorbic acid. Once the stains are gone, add 2-3 doses of a quality
metal treatment. Allow to recirculate for 6-8 hours before storing the pH
and chlorine levels. Good luck and I hope that the information proves
helpful.
Sincerely.
Alan Schuster, 2/23/2005
►
Yellow Staining
After Salt Addition?
We have a 16 x 32 inground
pool with a "SALT" system. We have had to add salt in November and December
and on both occasions once the salt was dispensed it has left a discolored
stain in the area where the salt was poured. The color is not black but a
light brown. The company where we purchased the pool has been of minimal
help. If you have the slightest bit of information please let us know as
this pool is only 5 months old and I am trying to save the liner.
Thanks.
Nameless, 12/31/2004
The staining
that you are describing is not something normal or inevitable.
The salt could have been of industrial quality and contained trace metals such as iron
(yellow prussiate of soda added as an anti-caking agent), the pool water
contained low levels of iron and, perhaps, the addition
of the salt and the resultant high TDS caused the iron to precipitate or the
salt was not distributed around the pool and/or was allowed to remain in
prolonged contact, without the benefit of being stirred.
Always use a food or water softener grade of salt.
Never use rock salt!
In either case, I would try adding a dose of a metal treatment to the pool and
try to remove the stains (most likely iron) by applying acid. To do this
take a white sock with 1/2 pound of pH decreaser powder and drop it onto the
stained area. Leave it in place for a few minutes and slowly move around
with the vacuum pool. Hopefully the acid will dissolve the stains.
You can also try a similar technique using oxalic acid. Periodic addition
of a dose of mineral treatment will help prevent staining and, in addition, help
keep the
salt chlorinator plates free of
scale deposits. I hope that this information will prove helpful.
Best wishes for the new year!!!
Sincerely.
Alan Schuster, 12/31/2004
►
Where Did The Copper
Come From?
I have a 14,000 plaster pool with a heater and
was recently troubled with some discoloration. The dealer found 1.3 PPM of
Copper. I never used a copper algaecide. So where did the copper come
from? Please help. Thanks.
Larry P., Clearwater, FL,
2/4/2003
It would appear that you have
dissolved some of the copper heater core. This is a result of low pH
conditions over an extended period and can be confirmed with a
Copper
Test. If your pH is too low, you must add something to the water
before raising the pH. Add a double dose of a quality Mineral Control
Product and recirculate for a few hours before raising the pH or total
alkalinity. This product should complex (chelate) the copper and avoid
further problems. If you are using TriChlor tablets there is a
tendency for the pH to drop over time.
Test the pH several times
weekly, at the very least. If you have an inline chlorinator, make sure
that it is located after the heater and filter - NEVER BEFORE! I hope that
I have been helpful.
Sincerely. Alan
Schuster, 2/4/2003
|
Visit The Test Equipment Store, for all your needs. |
►
Questionable Stain?
I have a 20 X 40 vinyl liner pool with a very
large sand filtration unit but I use
Zeobrite filtration media
instead of sand. (Awesome stuff by the way). About mid season
last year I installed an Ionizer (copper and silver type) on my pool to reduce
the amount of chemical use. Near the end of the season I started developing a
blackish stain in the creases of my pool (where the pool walls meet the bottom).
I've done some research and believe it is a mineral stain from the copper or the
silver used by the ionizer. I have discontinued the use of the ionizer and am
simply using a chemical approach to sanitizing the pool and the stain growth has
stopped. First, how do I get rid of the stain? Second, if I reintroduce the
ionizer to the mix, how do I keep it from coming back?
Tim Y., 5/15/2004
It could be
due to heavy metal stains or possibly algae. The trick is in narrowing the
field, inasmuch as treatment is quite different. I suggest that you try
something simple. Place a half pound of pH reducer powder in a white sock.
Shut off the filter and drop the sock onto the stain. Position, as needed,
with the vacuum pole. Leave in place for about 15 minutes. If there is
improvement, the problem is positively due to a heavy metal: iron, copper or
manganese. If this does not work, try the same thing using oxalic - a product
that some pool dealers carry. If the stains are removed, add a double dose of
a quality metal treatment now and add another dose monthly or whenever new
water is added. If this fails, it is possible that the problem is black
algae. Black algae is a resistant type and will require a regimen to remove.
You will need to boost the Free Chlorine level to 10 PPM, add an initial dose
of a polymer algaecide, add an initial dose of a quat algaecide and lower the
pH to 7.0-7.2. Redirect the return flow to improve the water circulation in
the affected area. Use a scrub brush on the stain, in order to expose the
sub-surface to the chemicals. If you have to use a metal treatment, it
will create a problem with the ionizer. The product will complex with the
copper and reduce its algaecidal action. I suggest that you use a polymer
algaecide, for at least a few months, should you resume use of the ionizer.
I hope that this information proves helpful
Sincerely.
Alan Schuster, 5/15/2004
►
Using Scouring
Powder?
I have a stain around my
vinyl pool. Can I use scouring powder on it to get out the
borderline stain? Is this true or will this destroy the liner? What are your
thoughts on this? Sincerely.
Michele, 8/6/2006
The pattern on a
vinyl liner is only printed on. If you use something like scoring powder, you
could remove the pattern along with the stain. Abrasive cleaners are
never recommended for use on vinyl liners! Your best option
would be to use
BorderLines. This product will allow
you to apply a new border, right over the old pattern. I hope that this
information will prove to be useful.
Sincerely. Alan Schuster, 8/72006
►
Tan & Brown Stains?
We have a 5000 gal
fiberglass pool with heater, that slowly develops stains (brown or tan) on
walls, pH 7.4, TA 120. These stains can easily be removed by a stain remover
(concentrated ascorbic acid), together with a metal treatment. After
treatment, pump is run for 12 hours then filter is backwashed and new DE
added. We treat this problem when it becomes unsightly, approx every 6 weeks.
Are you aware of any chemical/product that could be added on a continuing
basis that would prevent this staining. It would be nice to have pool walls
clean all the time. Could corrosion from heater be causing problem? Any other
possible cause of problem? Thank you.
Tom K, 3/22/2004
The color, of
the pool stains, is not consistent with copper, so I would rule out the heater.
However, it is consistent with iron and so is the treatment that you have used.
I suggest that you have the pool and source water tested for iron. Any
level can be a problem. Iron can be present, even if the test results are
negative, due to interference from other chemicals that might have been added or
from the fact that it is on the walls and no longer present in the water.
It sounds like iron, so I suggest that it be treated like iron. The
recurrence could be due to not having added enough of the metal treatment or
having added makeup water. Add a dose of the metal treatment now and add
an additional dose monthly or whenever new water is added. Fiberglass has
a negative electrical charge and can attract positively charged metallic ions,
causing the development of a stain. The periodic addition of a metal
treatment should help negate this effect and
help keep pool stain free. I hope that the information will prove useful.
Sincerely.
Alan Schuster, 3/22/2004
►
Gray-Black Staining?
Wonderful website!
I am desperate. We have a 4 yr old gunite pool (16,000 Gal) we inherited when we
bought the house 1 year ago. The pool has a cartridge filter and a heater.
Although we don't use the pool in winter, we have it maintained just like in
summer, so we could swim at any time, if we wanted to heat up the water (but we
haven't this year). We have been using a pool company to clean and treat the
water. We are on their regular stain treatment program. Never had any stain
problems. Until this winter. First it started in the area near the
drains in the middle of the pool, a big dark grayish/black area developed.
Now within 2 months almost the whole pool is covered with the gray black stuff.
I tried your pH minus in the sock trick - it worked. So I had the pool guys give
me 10 more pounds of the stuff and started at 7 am this morning with the tube
sock, trying to move it around the pool. The pH minus is dissolving very
quickly, when I move it around on the pool brush with a tube sock. By now the
whole pH of the pool is at or below 6.8 and all the pH minus is gone but
probably around 2/3 of the pool is still stained. How should I proceed? Any ideas why all of the sudden the pool would start staining like this and the
stain spreading over the months? We are in Houston, Texas and we have lots
of pines around us and lots of wax myrtles. We do have an automatic cleaner and
clean the skimmers and scrub the pool 2x a week. Water was filled up 4
inches 3x times last summer with no immediate effects on the staining. Thanks in
advance for your help.
Marita S., Houston, TX,
2/17/2005
The problem
could be caused by something in the water: iron, copper, manganese.
Have the water tested. You may have subjected the heater to the corrosive
effects of chlorine and low pH. If the acid made a difference, the problem
is not algae or something due to the trees. At least not entirely.
Tree stains and algae are best removed by shocking. Mineral stains will
not come off with chlorine! I suggest that you drop the pH to about 6, bypass the filter if possible. Add a
double dose of a metal treatment and use the scrub brush. It sounds like the
problem was too big for the sock treatment. Let me know how it turns out. Good
luck!
Sincerely.
Alan Schuster, 2/17/2005
I just stopped after 10 solid
hours and 23 pounds of pH minus. I have not run the pump at all today, since
there is no way to bypass heater and filters. My pH test kit only goes as
low as 6.8, but it is much lighter than that colour, so I assume the pH is way
down. After I emailed you, I used another 10 pounds of pH minus in the
sock and kept spreading it around, but the stuff really only came off
immediately underneath the sock this morning. I have also scrubbed my
heart out, and it appears overall that probably 3/4 of the staining is gone or
has lightened up, which leaves me with light shadings of gray in some areas.
The pool guy only left me a pint of metal product. I had asked him for 3.
So I went ahead and used the one pint I had, since I am worried about the
dissolved stuff resettling. I was thinking of leaving the pH low until
tomorrow PM and adding some more metal product in the morning and scrubbing
again really well. I won't run the equipment until the pH is rebalanced.
Do you think this will damage the plaster? It is already kinda worn off on
all the corners by the pool cleaner and I had to patch 4 spots where the gunite
was showing! We did have some green algae early this summer and it does
appear that the very first black/gray stain (1ft diameter by the drain) appeared
within a few weeks after the algae were gone. It seems like it disappeared after
that so. Could the algae treatment the pool people used have caused this
and, if yes, how could that have been avoided? And if it did, why would it keep
spreading gray/black stuff for months after? And why is that chelated
metal treatment they are using monthly for iron, copper, manganese etc not
working? I know, lots of questions, but I am a pool novice and so tired
and frustrated I am about ready to fill the thing with dirt and plant
flowers! Thank you so much for your support and I have referred
your web page to our pool guys!
Marita S., 2/18/2005
It is not
algae. Algae wouldn't come off with acid. Yes, the acid will etch the surface
a bit. Try and keep the chlorine level low, as long as the pH is under 7.0, in
order to help protect the heater. The overall acidic conditions should
even out the appearance. If some spots remain, try locating a stain treating
accessory and use it to siphon an acidic solution onto any remaining stains. I
can't comment on why the products didn't work, as I have no information relative
to their content. Possibly enough product was not added. It is
possible that the algae treatment caused the start of the problem. Copper
can stain masonry surfaces, especially in the presence of high levels of calcium
hardness. Adding some metal control product, after the algae is gone, can
help minimize the possibility of staining. Good luck.
Alan Schuster,
2/18/2005
Boy, Alan! Do we have a
sparkling pool this morning! The pool guy just came by and couldn't
believe the change either! Your help REALLY is appreciated, recommended
your website to everyone I know has a pool. Thanks a million.
Marita S., 2/19/2005
I guess it
doesn't get much better that this. Just make sure that you add a dose of a
metal treatment monthly and prior to adding an makeup water. If you use
algaecide, try a polymer based product. Glad that it all worked out.
Regards,
Alan, 2/20/2005
►
Grayish Spots In Fiberglass Pool?
I have a 18 by 36 fiberglass in ground pool, and
I have noticed lately that there is round grayish black spots all over the
bottom, I tried scrubbing them off, but nothing, I have shocked it and put in
algaecide and nothing happens, what can I do to get rid of these.
Robin M., 8/29/2003
The stains could be
due to a metal in the water: possibly iron and/or copper. Cobalt can be a
problem with older
fiberglass pools.
If the problem turns out to be cobalt, there are products to try.
However, they may not work and the only recourse might be a refinishing.
Newer fiberglass products seem not be
affected to the same extent, as older
technology finishes.
Try this and, hopefully,
it will remove the colored spots and stains.
Add 1/2 pound of pH reducer powder to a white sock, shut off the filter and
drop onto a stain. Position using the vacuum pole and leave in place
for about 15 minutes. Move the sock around with the vacuum pole after this
period. If the stain is gone, repeat elsewhere, as needed. Once the stains
are gone, add a dose of metal treatment, in order to avoid a recurrence.
If not try the same technique using oxalic acid - some pool dealer carry the
product. Try placing a few vitamin C tablets on the spots. If this
works it indicates that ascorbic acid will work and that it is a metal stains.
Again, some pool dealers carry an ascorbic acid product. I hope that I
have been helpful.
Sincerely. Alan Schuster,
8/29/2003
►
Black Spots?
First of all the basics: 22,000 vinyl liner pool with skimmer and
main drain, Chlorine treated Sand filtration. The pool gets black mud
looking spots. They can easily be brushed away, but return. I usually
use a copper based algaecide. It has given some relief in the past but seems
ineffective now. We keep our pool open year round but only swim in summer, we
live in Atlanta. Have you got any ideas? Sincerely.
Mike G., Atlanta, GA, 3/10/2004
My best guess is
that it is not black algae: this type of algae is very difficult to remove
and will not simply brush away. It is possible that copper can cause some
black stains, especially if the pool water is high in calcium hardness, although this
is unusual with the proper use of a chelated copper algaecide. I suggest
that you discontinue use of the copper algaecide and start using another type,
inasmuch as you stated that it seems not be effective. My choice would a
polymer algaecide. It is more expensive, but worth the price. Try
this on the stains. Put 1/2 pound of pH reducer in an old white sock, drop
onto a spot. Leave in place for a few minutes and move around with a
vacuum pole. If improvement is seen, this will confirm that it is a
mineral problem and not algae. Repeat elsewhere as needed. To help
prevent a recurrence of the problem, add a double dose of a quality mineral
remover. There are pool stain scrubbers available to help remove difficult
spots. You might find more information in other areas of the
archives. I hope that I have been helpful.
Sincerely.
Alan Schuster, 3/10/2004
►
Gray Stains?
I have a
large in-ground pool/spa, 7 years old, kidney shaped, about 30,000 gallons.
It has had a Copper Ionization + ozone system on it for about 5 years.
Over the years, the pool service did not maintain the pH properly and the pool
has developed gray stains. A drain and acid wash is recommended by my pool
service but I am reluctant to proceed due to the expense and the impact it has
on the pool surface finish. My pool technician, has suggested that he has
been successful in treating stains like these with the addition of Muriatic acid
to the water. I am willing to give this process a try as it appears cost
effective and should not damage the finish. I would like to try the
treatment on the spa first, and see if it is successful. If yes, than I would
like to do it to the whole pool. What are the pros and cons to this
approach? How much Muriatic acid needs to be added for success? My spa is
8 feet in diameter. How many gallons of acid for the 30,000 gallon pool?
How long should I let this circulate? Are there different strengths of
Muriatic acid? Which one should I use? What is the best way to restore the
water chemistry after this operation? Thanks.
Minoo B., 12/1/2003
I frequently recommend that a pool or spa be subjected to an acid bath as a
means of stain removal. Basically it dissolves the top surface and hopefully
takes the stain with it. Lowering the pH will subject the metal parts to
corrosion, including the heater, if chlorine or bromine are present. Therefore,
treatment should be in terms of a short period of time - a day or less. You
have to add enough acid to lower the pH below lower pH readings on the testers.
A pH of about 5.5-6.0 should suffice. Use the brush to scrub the surface.
Bypass the heater, if possible. Once the stains are removed, add a dose of a
quality metal treatment, in order to help avoid a recurrence. Restore the pH
and TA. Because the addition of the metal treatment could interfere with the copper
being introduced by the ionization unit, I would recommend using a
polymer algaecide for a month or two, while the copper ion content is
re-established. I hope that this information proves helpful.
Sincerely. Alan Schuster, 12/1/2003
I used
your recommendation and the pool/spa surfaces are now to almost all-new
condition. Thanks. There is one problem I am having that I have not been able
to solve. The pH continues to remain high (around 7.8 to 8), the TA is
fine, and repeated attempts by my pool service and me to lower the pH by
adding acid have not been successful. My pool service thinks that the
pool/spa surface areas are still leaching chemicals and are planning on adding
some chemicals that will help. Any suggestions based on your
experience? Sincerely,
Minoo B.,
12/4/2003
It is
possible that the walls are leaching into the water and causing the pH to
rise. To help prevent this, check the calcium hardness level. If the level
is below 200 PPM, raise it to that level. If the calcium hardness is above
200 PPM, the answer to the problem may lie elsewhere. I hope that I have
been helpful.
Sincerely. Alan
Schuster, 12/4/2003
►
Pool Stain
Problem?
Alan, We
have a 30,000 gal. in-ground pool that is filled from a private well on an
ionization system with a sand filter. About (2) years ago, we started noticing
dark stains in the pool. At first it was only on the fiberglass steps, but now
we also have it forming on the vinyl especially in the deep end. By reading
other articles by you, we feel problem is caused by iron from the well water
(have noticed some staining in house toilets). If this is true, will adding a
solution to the pool to remove these stains hurt the ionization system? Thanks.
Tommy,
5/16/2003
Yes,
the addition of a mineral treatment can affect the copper ions. Have the
water tested for iron and copper. The copper at a few tenths of a PPM
should be from the ionizer.
Any iron would be undesirable! The
iron should be treated with a mineral treatment: there is little choice in the
matter. Some of the ionizer manufacturers will advise you to add a
dose of a chelated copper algaecide to maintain the effectiveness of the copper
ion concentration. Read the instruction manual for comments on this
topic. If it were my choice, I would forgo the addition of the copper
algaecide, inasmuch as we are not certain about the cause of the staining.
Instead, I would add a quart of a 60% Polymer Algaecide and continue with the
maintenance dose for another few weeks. By that time, the copper
concentration should have reached a new equilibrium. I hope that the
advice proves helpful.
Sincerely. Alan Schuster, 5/16/2003
►
Brown Stains?
I have a 18x36 inground
pool. Rectangle with radius corners. The pool is 6 years old.
We have brown-colored stain on the pool liner. Is there any way to remove this?
What caused it? We have never had this type of staining previously.
Thanks.
Becky S.,
5/7/2004
It is
difficult for me to know, with any certainty, what has caused the vinyl pool liner
to become discolored and stained. The problem could
be stains from leaves and debris or a stain from algae. If the pool was
just opened, these possibilities are likely. The colored stains could, also, be
caused by the presence of heavy metals such as iron or copper. Having the
water tested for iron and copper could shed some light on these
possibilities. If you think the problem is leaves or algae, it,
should be removed by shocking the pool water. Raise the Free Chlorine
level to 5-10 PPM. This should show improvement within a day or so. If
the problem is minerals, you can try this as a means of confirmation. Put
1/2 pound of pH reducer granules in a white sock. Shut off the
filter. Drop the sock onto a stained area and leave in place for 15
minutes. Use the vacuum pool to move it around. after 15 minutes. If
improvement is seen, the problem is definitely minerals. To treat the
entire pool, it will be necessary for the pH to be dropped to approximately
5.5-6.0. This will dissolve the stains. Use the brush to speed
things up. Afterwards, add 2-3 doses of a quality mineral treatment, in
order to complex the minerals and help prevent a recurrence. Browse
through the pool staining or algae pages for more information on this
topic. I hope that I have been helpful. Good luck.
Sincerely.
Alan Schuster, 5/7/2004
►
Stained Gunite Pool?
Dear Alan, I tried your sock trick with pH decreaser
and it worked on the stain. My problem is the pool store said that if I use to
much muriatic acid to lower my pH to 5 it would destroy the surface of
my gunite pool. They are in the business to sell chemicals. Please advise
as soon as possible. Thanks.
Bill L. from Florida, 11/11/2003
You'll need to fill in some of the blanks. The sock trick
worked? Did it work in a spot or everywhere? Is the stain local or
overall? You may have to just lower the pH into the mild acidic ranges and
that should no permanent damage. It would be like an acid wash. I'll get back
to you after your reply.
Sincerely, Alan Schuster,
11/11/2003
I tried the pH decreaser on the steps of my pool and
also in the deep end I believe the stains to be iron since I use well water to
fill the pool. I used a vitamin C tablet and it also removed the
staining, but not as quickly. How low can I lower my ph without adverse
effects? Also can I use muriatic acid since it is much less expensive then
dry acid. I hope you have enough info. Sincerely.
Bill L., FL, 11/12/2003
You must
have the pool and well water tested for iron. You will need to add one dose
of a quality iron treatment, for each one PPM or fraction - ASAP! In the
future add more after each addition of new water. This will not remove the
stains, but should help prevent more. From what you are saying, it is
apparent that acid will remove the stains. That being the case, I suggest
that you allow the chlorine level to drop to just a few tenths of a PPM.
Lower the pH to 6.0-6.5, by the addition of muriatic acid. In this
application, there is no benefit in applying dry acid. It will only cost more
and make zero difference in the corrosion. Only the pH matters. Once the pH
is lowered, use the brush to scrub the stains. Keep the filter operating
and, if possible, by pass. Periodically check the pH to see if more acid is
required. The acid will etch the upper surface of the walls and by doing so
will help remove the pool stains. The same etching would result from acid washing
the pool. The lower the pH - the faster the removal process. Once the stains
are removed, add another dose of iron treatment, prior to raising the pH. If
you can find a source of oxalic acid, it might speed things up, if you add it
just prior to adding the acid and while the chlorine level is very low. This
chemical will discharge all of the chlorine in the pool and will make a shock
treatment necessary to restore a chlorine level, after the pH has been
optimized. However, before shocking allow at least 6 hours for the iron
treatment to work. I hope that this information will prove helpful.
Sincerely. Alan Schuster,
11/12/2003
Dear Alan, thanks for the advice. I did as you
suggested and it worked out great. The walls of the pool look great. I
will use an iron treatment, in the future, whenever I put water in the pool.
Thanks
again. Great site. Good advice. Sincerely.
Bill L., FL, 11/15/2003
►
Brown Walls And
Bottom?
Alan, Your
pH-reducer-in-a-sock trick did WONDERS for our 7 yr old vinyl lined pool
BOTTOM. Within literally minutes, the brownish stains on the bottom
disappeared. Problem: The stains are still on the
sides of the pool, however, and we cannot seem to get them off. Our
attempted solution. We tried rubbing the sock on the sides,
but were unable to stand there long enough for the trick to work. We treated
the whole pool, as you suggested, but the stains persist, only on the sides.
Any other suggestions? Sincerely.
Stephanie M., Edmond,
Oklahoma, 5/17/2004
Stains on a vinyl liner will rarely ever respond just to the addition of a metal
treatment. Acidic water conditions are usually required. Such products can
help avoid further staining, but may not act upon a current stain. The fact
that the sock worked shows that the problem has a solution. It is case of
lowering the pH of the entire pool to below 6.0. From your description, it
appears that iron stains are the problem and this treatment should work.
However, it may work faster and better, if you allow the chlorine level to
bottom out and add some oxalic acid, after the pH has been lowered to about
6.0. Once the stains are gone, add another dose of the metal treatment.
Thereafter, add a monthly dose or whenever new water is added. Good luck
and enjoy the summer.
Sincerely. Alan
Schuster, 5/17/2004
Alan, I LOVE your site, and
have told all my pool owner friends about it! As a follow up to my earlier
question, we FINALLY got all the stains off of our pool. In fact, it has
never looked better. We followed your advice about the pH reducer in a
sock, and that got rid of all the bottom stains. Then the local pool supply
store told us to rub a lemon/orange/vitamin C tab on the stains to see if that
got them off. They started coming off instantly, so we went ahead and bought
their stain remover product that was sheer concentrated ascorbic acid.
(Confirming what you said about acidic conditions being necessary). We did
not follow the instructions and broadcast the product in the water; rather we
put it in a sock again and rubbed it along the sides. Thought the vitamin C
thing might help someone else. Thanks a million!
Stephanie M., 5/18/2004
►
Stains
From H--l?
Alan: I have a gunite pool built in 1959. The previous
owner's neglect has created brownish/black colored stains from leaves and there is
also a very light greenish blue colored stain. I drained the pool thinking a
muriatic acid wash would take care of this. I was so wrong.
Using a 4:1, acid to water, it did not even scratch this stuff. I need to get water back in the pool because
of the massive amounts of rain we've had. Please give me advice on
chemicals, treatments, etc. I can't really afford to refinish and I was told
that paint, because of the cratered surface, would peel quickly.
No Name, 5/13/2003
The brownish
stains are probably tannins from the leaves. Fill the pool up and a double
dose of a quality mineral treatment, just in case the pool stains are more than
tannins. Add shock and boost the Free Chlorine level to 5-10 PPM.
Tannins will be destroyed by the chlorine. Keep the Free Chlorine level
elevated until the dark stains are removed. Keep the filter operating
and use the brush. After these stains are removed, you will in a better
position to access the appearance of the pool. The greenish stains could
be algae and/or copper. If it is algae, the chlorine will take care of
it. I am no expert on painting the pool, but at the very least you will
have to thoroughly clean the walls before painting them and this is a good start
on that road. Let me know how the first part turns out and we'll try to
deal with the remaining problem. Good luck and I hope that the information
proves to be helpful.
Sincerely.
Alan Schuster, 5/13/2003
►
Rusty
Stains On Fiberglass Bottom?
Dear Alan, I recently had a
fiberglass pool put in.(4 months ago) A short time later I saw my first couple
of stains. One is a 2 inch streak 1/4 inch wide, my pool man who only ads the
chemistry thought it might have been from a nail. I had a house built right next
to the pool. The others seem more round and streaks like a meteor they are
fairly small but I'd like to get rid of them without destroying the gel coat on
the fiberglass. Any suggestions are welcome. The pool manufacturer
thinks the pool guy might be adding the chemicals that settles on the bottom and causes these rust looking
pool stains. Thank
You.
Kris, 4/27/2003
None of the
chemicals that the "pool guy" is adding should be capable of creating a pool stain
problem.
There are two likely causes of a discolored or stained pool. The source water added to the
pool contains iron or other heavy metals. You can confirm this by having
the
pool
water
tested: most pool professionals offer complimentary water
analysis. The other equally likely possibility is a foreign object. Start by
adding a dose
of a quality Mineral Treatment Product. This will complex with
iron and help prevent further staining. To remove the stains, a good option would be to use
a stain-remover accessory. This inexpensive device is available at many pool
stores and will
allow you to siphon a solution onto the stains. To make a suitable
solution: to a 1/2 gallon of water, in a plastic container, add 1 quart of a
quality Mineral Treatment Product and 1 quart of muriatic acid.
Make
sure that you wear rubber gloves and eye protection! Because your pool is
still under warranty, I would discuss this treatment with the builder, so as not
to risk voiding the warranty.
Use the stain-remover accessory to siphon the liquid onto the stains.
Afterwards, adjust the pH, as necessary.
Fiberglass
pools have a negative electrical charge and can
attract positively charged metallic ions, possibly causing the development of a stain.
The periodic addition of a metal treatment should help negate this effect and
help keep pool stain free.
I
hope that I have been of assistance. Good luck
Sincerely.
Alan Schuster, 4/27/2003
►
Origin Of Big Brown Stain?
I have a pool customer who has an inground
fiberglass diving pool. Our service man opened the pool to discover a big
brown stain in the deep end. He said that it looked like it was
bleeding through from the other side and that it seemed to be coming from a
nest of worms? I was wondering if this is possible and if so, how
would we go about fixing it? Your help is always greatly appreciated!
Thanks.
F. K., Tennessee, 4/27/2007
That would
most likely mean a leaking pool, if there were direct contact with the
underlying soil. Is there a significant water loss? Otherwise, it is on the
surface or in the gel coat and not through to the soil. I would try some
ascorbic acid, to see if it is a metals problem or some trichlor granules to see
if it is organic matter. Do them at different times. Probably, an
animal got in and you are looking at its decomposed remains. Possibly,
there is a defect in the finish and it is allowing water to penetrate to the
fiberglass. A little experimenting should narrow the possibilities and
point to a solution. I hope this proves helpful.
Sincerely. Alan Schuster, 4/27/2006
►
Worked Immediately?
I have the light brown
stains on a vinyl pool. An oxalic acid product Stain Treatment worked the
best. Immediately the stains disappeared. The problem is I can't find any
locally. Can you tell me of any other similar products that national pool
places would carry? Thanks.
Maria, 5/20/2004
Oxalic acid
be very effective in removing iron stains, especially if you can get the
chemical to the strain. It is functioning as an acidic reducing agent.
While many pool dealers carry the item, it is not in every store. If you
can't find oxalic acid, perhaps, you can find ascorbic acid (vitamin C).
It works in a similar manner. Good luck.
Sincerely.
Alan Schuster, 5/20/2004
►
The Tough Last
10%?
Without a doubt the very best
site I have seen yet on the problem of pool stains. We opened our 3 year old vinyl 20-40
pool and had a ton of dead leaves and junk that ended up on the bottom.
Pulled out as much as possible and then
vacuumed up all the brown "dirt" junk on the bottom. 90% came right up
but some did not, it is as though it is "painted" on to the
bottom. The interesting thing is that it follows the pattern of the vacuum
attachment,
that is, it looks as though the brownish color was "rubbed into" the
vinyl. The pool water is incredibly clear. The stuff will not vacuum up
easily. Using a rubber gadget, sort of like a large eraser, allows me to
rub some of it off but this will take forever. Does this sound like a
metal stain (iron). I did have some brown chalky dirt on the plastic
returns in the pool which I understand is a sign of metals but the stains have
definitely been
"rubbed into" the vinyl which I would assume is more like a vegetable
type or tannin stain. Anyway, I am open to suggestions. Thanks.
Ray S., 6/19/2003
Obviously tannins would have been
my first choice. The circumstances all point to tannins as the cause.
The statement that the water is clear leads me to believe that the
chlorine reading is acceptable. The fact that you can rub it off
eliminates the possibility of it being a fungus on the reserve side of the
liner. That does leave open the possibility of iron and or other metals.
Try this!!! Put 1/2 pound of pH reducer powder in a white sock, shut off
the filter and drop onto a stained area. Leave in place for 15-30
minutes. Move with a vacuum pole and, if improvement is seen, the problem
is definitely minerals. You might be able to treat the problem by
repeating this procedure. If the problem is mineral you will need to add a
double dose of a quality mineral treatment, in order to help avoid a
recurrence. You can use a stain removal accessory to scrub the remaining
stubborn spots. If the sock trick, does not work, I am inclined to believe
that it is a plant-derived stain or early stages of a resistant algae. I
would treat this on the basis of being black algae and add a polymer based algae
and boost the Free Chlorine to 10 PPM. I hope that this leads to
success. Refer to the archives on Black algae for additional
information. Thanks for the encouragement. Enjoy the summer.
Sincerely. Alan Schuster,
6/20/2003
►
All Gone!!!
We took your advice and used
metal out product. Brown stains on steps are gone! I am so disgusted when I
think of what we have done this summer and last! Two different companies tested
the water for metal and said there was none! How often, as a general rule,
should be use the metal out product? The bottle did have a maintenance dosage
amount recommended. Thanks so much!
Debbie H., Montgomery, Alabama, 10/26/2003
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