Need answer to algae question - how much poly?

[waterbear]

Posted below, but no one responded. If anyone can just respond briefly, I'd appreciate it.

Have 22,5k gallon IG, plaster, SWG. Have mustard bloom. Raised ch to 15 for a few days, it left briefly but came back.

You stated in a later post that your CYA tested at 60 ppm. If that is the case it is entirely possible that you did not get your FC levels up high enough. Ben's best guess CYA chart recommends 20 ppm
http://www.poolforum.com/pf2/showthread.php?t=365

I would give it one more try with chlorine and this time make sure you are at or above 20 ppm!

[Watermom]

That was my thinking, too. That is why I asked him what his cya level was.

[SoCalBoo]

Once I get ben's kit, I'll have a better read on the CYA. The good news is that the mustard is much, much less than it was, so the superchlorination with bleach obviously worked, albeit not completely.

By the way, seems like the autopilot is calling for a rather high CYA level at 60-80...anyone have experience with using a lesser level with the autopilot? Or maybe that level is just fine and my experience is with lesser levels....

Thanks for the help.