I've been struggling with an issue for a few days now and, after getting mixed advice from Pool Stores, etc, I thought I'd turn to a forum to see if anyone has experienced this issue or could offer up some new ideas.
Basically, I opened my pool over the Memorial Day weekend and it was green. I lacked some things in the pool closing, regardless, the water is sparkling clear now. I've tested my water and it is balanced. Obviously I have some residual green algae stains (I've been unable to confirm if it's black, but I didn't see any 'heads', so I'm assuming it was only green). The stains do not react to acid, so I know they're organic - some have bleached out when using shock that was not brushed immediately.
For 3 days in a row, I shocked the heck out of my pool, both the FC and TC were > 10. You'd think with chlorine levels this high it would remove the stains, but it isn't. It's hard for me to tell if the stains have lightened at all, but I do notice that when I brush with a steel brush, I do see some brown dust come up - I'm assuming this is dead algae?
1) Should I keep shocking and maintain very high levels of chlorine in an attempt to bleach these stains out? Will they ever bleach out completely?
2) Is there anything else I can do accelerate this process? I don't believe there's any magic solution that will rid these stains.
Here's a link to my Google Picasa website to show you what I'm talking about:
I would greatly appreciate any insight or advice you guys could give me.