6% bleach raises Chlorine level how much??

[Darrenmv]

I must be stupid because I know this is already somewhere on this site, but for the life of me I cannot seem to find it.

Looking for the basic formula for 10,000 gallons.

Thanks,
Darren

[PoolDoc]

A gallon of 6% bleach adds 0.5 lbs of Cl2 equivalent.
10,000 gallons is 83,000 lbs, or 1/12 of a million pounds
Add one pound of A to a million pounds of B, and you have approximately one ppm of A in B

In your case, it's (0.5 x 12) or 6 ppm of chlorine per 10K gallons per gallon of 6% bleach.

So, the formula is, "1 gallon of plain 6% bleach increased the chlorine in 10,000 gallons of water by about 6 ppm".

[chem geek]

You can also use The Pool Calculator to calculate dosing. You will see that one gallon of 6% bleach raises the FC by 6.17 ppm in 10,000 gallons since 6.17 is the "trade %" which is the % available chlorine by volume. 6% is the weight % of sodium hypochlorite itself as found in an ingredients list and 5.7% is the "% available chlorine" (by weight) which is also printed on Clorox bleach bottles. Yes, all these different units of measurement are confusing but fortunately they are close enough to one another to just go by a simple rule-of-thumb.