Using a Nature 2 system with the BBB method

[PoolDoc]

Good luck!

[tdkorson]

Overnight has made a big improvement! I suspect it will take several days of filtering, vacuuming, brushing, etc., but real progress is being made!

[PoolDoc]

Great!

[tdkorson]

BTW. I checked with the pool store, and the parts guy said that the impeller that I have a 3/4 hp impeller on a Hayward super pump.

[PoolDoc]

Yes, but is it a 3/4 UP-rate or 3/4 FULL-rate impeller?

Never mind -- I think you've found and fixed your problem. If it's working, it's working, and don't mess with it, unless you just like to tinker!

[tdkorson]

Success! The water is sparkling clear. The dead algae is all filtered out and vacuumed off the bottom.

Remaining problem - Lots of green stain at the water line and a fair bit of stain on the bottom off the pool. What is the best way to remove the stain?

[PoolDoc]

"Green stain" is generally live algae! Brush & chlorinate and do NOT let your chlorine levels get low, even for a second!

Greenish blue stains can be copper. That's a whole other deal.

[tdkorson]

I am documented red-green color blind, so forget what I said about green stain. I just asked my wife to describe the stain color and she says it is yellow with a slight brownish tint.

[PoolDoc]

At the water line -- pollen, dirt, lotion, metals are common causes.

At the bottom -- mustard algae.

Brush, chlorinate . . . and scrub the water line with a baking soda paste on a sponge. If that doesn't touch it, hold a vitamin C tab against the stain. If THAT removes it, it's metal based.

[tdkorson]

Vitamin C does the trick. Rubbing tablets on the stains just above the current water line got them all off, but the stains at and just below the water line and on the fiberglass steps remain. So it looks like I should try an ascorbic acid treatment.

Question. My fc is down to 0, ta is about 100 and CYA is 65, but my PH is 8.2 Should I lower the Ph a bit before using the ascorbic acid? Any advice about about the best sequestering agent to use?