"Concentrated" bleach -- what does that mean?

[OutWest]

I was at Home Depot yesterday and decided to check out their bleach. Much to my surprise they had different ones--for outdoor and indoor, a concentrate that said it had to be diluted, ya da ya da ya da. Nowhere on the label could I find the percentage of actual bleach (12.5% etc.) that has been discussed here in the pool school articles on chemistry.

Has anyone used this stuff? Is the concentrate too strong for pool use? I could see no additives listed on the labels.

 

[needsajet]

It won't be too strong for pool use, but I would not buy anything that doesn't have the % and manufacture date on it.

The most expensive bleach I've seen was in a spray bottle as "stone and brickwork cleaner" 3% sodium hypochorlite, 20 oz spray bottle for $7.99 (around $50 per gallon for 3% bleach)

2nd highest I've seen was "driveway cleaner" with 3% bleach and $20 a gallon.

You want 8.25% minimum and around $2.50 / $3.00 per gallon. Sometimes the same stores have pool shock (liquid) at 10% sodium hypochlorite and around the same price. Get the freshest you can find - manufacture date 16150 means 2016 and 150th day of the year. The highest I've seen is 12.5% and I've read that it's a practical manufacturing limitation that limits from being very much higher.

 

[pooldv]

+1 to not buying anything without the percentage clearly marked. It varies some by state but here is how it usually works. These are all the same product, just different strength.

6% regular bleach
8.25% concentrated bleach
10% liquid chlorine
12.5% liquid shock