Thanks a lot to aylad and Waterbear! Waterbear, you may be on to something with the iron/yellow water over blue liner idea, but so far the green is very faint and only really noticible on the (white) stairs and swim out. If the water hadn't been perfectly clear before I probably wouldn't even say that the water was green. The Metal product they sold me was SunGuard Metal-Out Plus, which I just found lists NO ingredients on the bottle (or the SunGuard website). . . hmmm. They had me use one quart for my 21,000 pool.

I think the "green" is less noticible today. pH is back up to 7.9 (tested w/ newly calibrated digital meter I had to get for household testing because we needed acid neutralizer for house - well is 4.9!!) which is what it was before last pH correction. After reading up on pH here on the forum, I've decided not to worry about that right now. Even with the (untreated) well water as fill last year, we were always on the high end 7.6-7.8 and had our lowest reading ever on opening this year - 7.5, so maybe that's just what my pool "wants" to be. I'm on my way to shock (bleach) and when my new super duper test kit gets here (K-2006) I'll check CYA, ALK, and FC/CC and adjust accordingly. Then I'll see where we are on pH. Thanks everyone!!