Mysterious Orange Stains In Inground Pool

[rickai]

We're having some problems with a stain in our 16 x 32' inground pool. The water has been tested and there is no hardness to speak of or metal content. One pool place said it might be algae, so we double shocked and used algae killer as they instructed...nothing changed. I found on one forum a topic that said it might be hard water stain, so I took their advice and used PH minus in a sock to treat it - BAM, cleaned a big spot in 5 minutes. I then shut off my filter and sprinkled ph minus over the stains, it settled on them and removed them. I turned the filter on, readjusted the PH (with plus) and thought it was all over. A few days later...BAM they're back. Can anyone give me a permanent solution to this? Also, a good definition of what it is, where it could have come from and how to prevent it would be great. Thanks for the help!

[gdayko]

If the stains keep appearing in the same localized spots, you might have a problem with your pool's rebar. i.e. The rebar beneath the surface of the gunite might be rusting, and the rust is seeping through to the surface of the gunite. We had a similar problem in our pool last year, started with some localized orange stains that got progressively worse. Tried everything, even covering with epoxy. But nothing worked, and the stains always reappeared. Unfortunately, the only solution for our problem was an extensive repair: drain the pool, chisel through the gunite, remove the offending rebar, apply sealant to the rest, and resurface the pool.

If this turns out to be your problem, the good news is that the repair only takes 2 days. Bad news is that it costs a pretty penny. But the pool will look great, and the problem will solved. You might want to ask a local pool service company to come out and take a look at it, rather than just describing it to the folks at the local pool supply store. Probably get a better assessment if a professional sees the probem for himself.

[ps558]

We're having some problems with a stain in our 16 x 32' inground pool. The water has been tested and there is no hardness to speak of or metal content. One pool place said it might be algae, so we double shocked and used algae killer as they instructed...nothing changed. I found on one forum a topic that said it might be hard water stain, so I took their advice and used PH minus in a sock to treat it - BAM, cleaned a big spot in 5 minutes. I then shut off my filter and sprinkled ph minus over the stains, it settled on them and removed them. I turned the filter on, readjusted the PH (with plus) and thought it was all over. A few days later...BAM they're back. Can anyone give me a permanent solution to this? Also, a good definition of what it is, where it could have come from and how to prevent it would be great. Thanks for the help!

If it was removed by PH decreaser it is a metal stain. It came out of solution from the water and stained the pool. Try looking into

Pool Magnet plus by Bioguard

Stain Free by Natural Chemistry

Metal remover by Sea Klear.

These will keep the metals in solution until you backwash.

Another trick is use a vitamin C tablet on the stain. If it removes it you use Ascorbic Acid from food stores

[Jeanieb]

I have orange stain or some form of algae on floor of my above ground pool. My chlorine, Ph, alkaline are all fine. I’ve scrubbed/brushed and heavy shocked, but it keeps coming back. 
Can anyone tell me what this is? 

[waterbear]

2 hours ago, Jeanieb said:

Can anyone tell me what this is? 

Not without more information. Please post a full set of test results (Free chlorine, Combined chlorine, pH, Total alkalinity, calcium hardness (NOT total hardness), and cyanuric acid (stabilizer) and how the results were obtained (strips, liquid reagents, dealer testing, etc.) If possible a water test for iron would be useful as would pictures of the stain. Do you use well water to fill the pool?  Saying that everything is 'fine' tell us nothing. The actual numbers are needed to see what chemical interactions might be occurring in your water.

Does superchlorinating (shocking) remove or lighten the stain? Does brushing remove it? The answers to these questions will help determine if the stains are metal or organic.

One test you can do to determine if it might be an iron stain is to put a handful of  vitamin C tablets in a clean cotton sock or similar cloth bag and hold it on the stain for about a minute. If the stain vanishes where the sock was you have a metal stain, most likely iron, and you need to treat with a metal sequestrant.