Info from Clorox on using their bleach for pools

[chem geek]

Thanks Evan. I also calculated 1 quart of 5.25% bleach in 6,000 gallons giving me 2.19 ppm chlorine (and using 7000 gallons would give 1.88 ppm chlorine).

This 5.25% vs. 6.0% (on a bottle of regular Clorox bleach I saw in the store a couple of days ago -- I'm pretty sure that wasn't Ultra, but I'll have to look again when I'm back in the store) vs. 6.15% on the MSDS for regular vs. 6-7.35% on the MSDS for Ultra is all confusing, to say the least. And it isn't explained by "bottle is Trade %, MSDS is Weight %" or anything like that.

I think that for practical purposes we can just ***ume that the percent listed on the bottle is Trade % and use the volume calculation in BleachCalc. I wanted to be more definitive about this, but even I recognize that I'm being way too picky about this. After I do some more checking at some stores to see what's really labeled on various bottles, I'll update my spreadsheet accordingly. It does seem that the 12.5% chlorinating liquid that I buy from a pool store (at $2.50/gallon) is indeed very close to 12.5 "Trade %". I don't mind paying a little more to carry fewer bottles (and I haven't found a convenient source of bleach that is that much cheaper -- i.e. less than $1.23 for 6.15% or $1.05 for 5.25%).

Thanks again for your help.

Richard