Thanks so much, guys, for your helpful and prompt replies. My pool is an inground, fiberglass pool installed in June 1998. It is 16 X 35 feet, with a constant depth of 4 feet. It holds 12,000 gallons.
Could you please give me your advice on whether or not this would be good AA to buy to use for my next stain treatment?
http://www.amazon.com/L-Ascorbic-Naturally-Fermented-Crystals-Vitamin/dp/B003EE5MZC
Unless you know something cheaper and better, that's the way I'm leaning. But I value your collective wisdom! How much AA do you think I'd need to add to 12K gallons to get rid of the stain?
I'm concerned that if I take the chlorine down to zero again algae may start growing. I understand that technically I don't have to take the chlorine level down, before an AA treatment, I would simply need to add more AA in that case. Any idea how much more?
If I did drop the chlorine down to zero again, how long after the AA treatment/sequestrant treatment do you suggest starting to reintroduce pucks/bleach into the pool to avoid restaining?
For sequestrant, I was planning on using Metal Free. Should I pour in a whole quart, and how long should I wait after adding the AA to add it? Also, do you know of any better, cheaper product I should use than Metal Free?
Thanks so much for your help with this, I really appreciate it!