I'd appreciate some help. I currently have some iron staining on my plaster SWG, 24,000 gallon 8-year old pool (cartridge filter). The iron comes from topping off with well water. I do not have borates in my pool now, and would like to establish them at 30-50 ppm. I have 3 pounds of ascorbic acid and two bottles of purple stuff and I was preparing to lift the stains, but would like some advice on how to combine the borates. Borax raises pH but there's also boric acid. Is it possible to use the vitamin C to lift stains, put in the purple stuff and then bring the pH back up to 7.2 using borax? Or a combination of borax and boric acid or a combination of borax and muriatic acid or washing soda?
If so, I'd like some estimates. I'm not sure how far down the vitamin C treatment pushes the pH, and I don't know how much borax, per pound, raises the pH. Assuming that I don't have enough pH room to put in all the borax I need (after vitamin c), perhaps using boric acid for some of it might work. Or, I could deal with the borax treatment before the stain lifting, or partially do so. For example, I could use muriatic acid and borax to get borates to 30 ppm and then use additional borax after the vitamin C treatment… A lot of variables, so any thoughts would be welcome.
CYA - 60-80