Brown staining in pool. Copper?

bryanw03

Member
Apr 1, 2024
5
butler, ga
I’ve had trouble for the past year with brown stains on vinyl, skimmer and floor jets. Putting citric acid removes the stains but I guess it just dissipates it for awhile because it comes back within a week. Pool store said it was high last year. I drained half the water 3 weeks ago, scrubbed the walls and refilled. Stains are back and Leslie’s said copper is at . 4, iron .1 phosphates 134.
My hardness and alkalinity are low since I’ve just filled up. They sold me Leslie’s no metal and said it will fix it but all I’ve ever read is drain it.
My question is do I try this or completely drain the pool this time.

I’ve also read that low quality salt could cause this. Water did look fine until I added more salt this week. I used Clorox brand salt from Walmart.

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Welcome to TFP.

Citric acid lifts iron stains. A sequestrant will keep the iron in suspension for a while but you need to keep on adding sequestrant or the iron will redeposit on the walls.

The only permanent way to remove iron from the water is to drain and refill it after an ascorbic acid treatment.


Clorox pool salt is often contaminated and we do not recommend its use.


 
Diamond Crystal should be fine. Water softener salt works great. Get plain, no additives.
 
It's important to put some kind of water filter inline when you refill (to prevent iron), otherwise you'll be back to square one. Ive got trace iron in my city water as well. Been thinking of adding an RV softener.
 

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I’ve had trouble for the past year with brown stains on vinyl, skimmer and floor jets. Putting citric acid removes the stains but I guess it just dissipates it for awhile because it comes back within a week. Pool store said it was high last year. I drained half the water 3 weeks ago, scrubbed the walls and refilled. Stains are back and Leslie’s said copper is at . 4, iron .1 phosphates 134.
My hardness and alkalinity are low since I’ve just filled up. They sold me Leslie’s no metal and said it will fix it but all I’ve ever read is drain it.
My question is do I try this or completely drain the pool this time.

I’ve also read that low quality salt could cause this. Water did look fine until I added more salt this week. I used Clorox brand salt from Walmart.

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The stains are Iron, most likely from the salt, though i see no test results. Add a cup of acid to a bucket 1/2 filled with pool water, that bucket must not of been used with chlorine, never mix chlorine and acid in the same container, it can be fatal. Run that around the perimeter of the pool, not just in 1 place, have the filter operating and after an hour or 2 take a water sample to your local recommended pool shop. Ask for a complete work up water test including metals.
This need to be done before you do anything.
With vinyl pools you have to be so careful with the chemicals you add.
Is there any chance the stone work on your pool surrounds could be the cause?
Keep your pH 7.2-7.4, that should allow metals to remain in solution.
Always before adding salt, even if your pH is correct, add a cup of acid as mentioned above.
If this is being caused by the pool salt, i would approach the supplier.
What is the foaming in the water from?
 
With *all* pools one must be cautious of which chemicals are added...and why? What response are you seeking? Did you test again to confirm you met your goal?

Keeping pH on the lower end of desired levels helps you avoid calcium scale (build up) when fill water is known to be high. Salt Water Generators tend to raise pH thru their action, and that can be totally acceptable assuming you balance that against your TA. I only need to add acid to my pool maybe 2x/year.

Knowing how metals get into the pool is muy importanto! Are you filling with water containing metals? How about using Copper containing products? Avoid them like the plague! check ingredient listing- it rarely says so in the name unless they call it "blue" or something with that. Blue Vitriol is the old old name for copper. If your fill water contains metals there are chems that can "hide" the metals in the water solution, but they can be a bother at times.

Don't add acid for no reason. Salt, if needed as shown by test results, can be added easily on its own, without risk. Best to brush it around to help it dissolve.

Maddie 🇮🇹 (13 year pool owner and never had algae)