Partial drain and metal staining...add acid after refill?

[Pfeifer6]

Our cya is over 150, and after fighting with the chlorine for over a month we realized it would be cheaper just to do a partial drain of the pool. There are brown stains all over the pool, which is fiberglass. After doing some research I tried vitamin C tablets on it and of course we were impressed with how it inmediately bleaches out the metal stain. Would you all recommend doing an acid wash while it's partially drained or adding acid to the water after it has been refilled? My concern about the acid wash is that we are not draining all of the water...just about 75%.

I would also welcome any tips on how to balance the water once its been refilled with city water. I've already looked it up online and skimmed over some instructions but if anyone has advice I'm open to that. Thank you!

 

[Richard320]

I'd treat it with Vitamin C first, and then pump that metal-infused water out and be rid of it.

After it's refilled, let it mix and circulate a while, maybe brush to speed it up, then run a full set of tests. Fresh fills are pretty easy to deal with, as long as there is no algae to fight. If you're unsure of the sequence, just wait until you have all the test results and post them and someone will be along soon to advise.

 

[Pfeifer6]

Thank you Richard. We started draining it before I posted and decided to do a full drain instead of a partial drain. Should we clean the walls/bottom BEFORE refilling it or just add Vitamin C to the water after refilling? Adding it to the water seems easier but I don't want to mess up fresh water with something that will affect the balance.

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So what I mean it, when you suggested adding Vitamin C...the water was already half gone. :-/

 

[Richard320]

Thank you Richard. We started draining it before I posted and decided to do a full drain instead of a partial drain. Should we clean the walls/bottom BEFORE refilling it or just add Vitamin C to the water after refilling? Adding it to the water seems easier but I don't want to mess up fresh water with something that will affect the balance.

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So what I mean it, when you suggested adding Vitamin C...the water was already half gone. :-/

I would do whatever I could to get rid of the stuff before refilling. Vitamin C and sequestrants don't remove the metal, they just isolate it. Sequestrant is to metal what the hard candy shell is to the chocolate in an M&M. Eventually it wears off and you will get chocolate melting in your hands... or staining on the pool walls.

Can you scrub it off with Vitamin C water? Then mop it up or pump it out or even use a shop vac on it? Like i say, anything to get rid of it before refilling will help. You might not even need sequestrants on the refill if you remove enough metal first.

 

[Pfeifer6]

Ok that's what I was thinking you would say. My husband wants to do a combination of vitamin C powder and the power washer. I'm looking into buying Vitamin C powder locally so we can get it done today. No fun having 90 degree weather and pool out of commission!