I have been fighting iron staining since my pool was installed (about 1 year ago). I have spent a fortune on staining products including AA. I accidently found that I can use PH down and sprinkle it down the side of the pool in the stained area. It works!! Then, if the ph gets too low, I add a little alkalinity (baking soda). I have found that if I keep my ph low (around 7.2) and my chlorine in the low normal range that the staining is less of a problem.
Is there any problem with using the ph down product to help with the staining? It is less expensive. I have a fiberglass pool and I do not want to mess up the gelcoat.
Thanks for your help!!