UnknownStain - Fiberglass Pool

[Skillset]

I opened my pool 12 days ago. Water balance looked pretty good. CYA held all winter at 55. Shocked the pool to about 15 and have not added bleach at all since opening and Cl is still staying at about 10. But, I noticed my pool is pretty stained - no longer just some spots. The stains are light though, only visible after the sun goes down, but there's a ton of them covering large areas.

I bought some of the Proteam Metal Magic product over the winter and wanted to use it tonight, but the label calls for the Ph being at least 7.5. So, I dumped some soda ash in to raise the Ph (it is currently 7.2) and was going to use tomorrow. Now, I'm not so sure if I should after re-reading some of your prior posts where you've indicated that the Ph should be low before using a sequester.

I'm not that worried because I know I can always throw a pound of ascorbic acid which will take care of the stains. But, maybe the Metal Magic will work without the acid and keep the stains away.

But, do you recommend using the Metal Magic at 7.5 (as the label recommends) or lower?

[mbar]

Go ahead and put the proteam metal magic in - it probably says to use it at a ph of 7.5 because it is very acidic itself, and will bring your ph down on it's own. I usually say that you should put your ph at 7.2 with sequestering agent because you want the water to be acidic to lift the stains. Since you have the metal magic I would try it first. If it doesn't lift the stain, then you can do the ascorbic acid - but give it a couple of days first, and if it doesn't bring the ph down to 7.0 or 7.2, then add a little muriatic acid, and keep the filter running 24/7. Good luck, and let me know how it goes.