Re: Changing over to BBB's
Hi Renlo
Plain 6% household bleach has about 1/2# chlorine gas equivalent in it; 15,000 gallons weighs about 125,000 lbs (8.3#/gal) or 1/8 of the mythical million pound pool. So you have 0.5 / (1/8) or 4ppm per gallon.
As a rule, to convert to BBB, you'll need to do some or all of your own testing, for two reasons. First, every time you go to a pool store, they will try to sell you stuff you don't need. Until you gain confidence in my BBB method, it's hard to resist those frantic warnings. Second, you will periodically need to measure higher chlorine levels than most pool stores can test. The FAS-DPD method of chlorine testing solves the 2nd problem, and having your own test kit solves the first. Taylor's K2006 or 2006C is least expensive kit that meets those standards -- Amazon links below.
Good luck,
Ben
Re: Changing over to BBB's
Be advised, that currently the seller for the K-2006 below in the Amazon link is NOT Amato Industries which is the only seller we recommend buying from. Some other sellers are substituting the K-2005 which you do NOT want. However, Amato is the seller for the K-2006C which is the same kit as the 2006 but just with larger bottles of some of the most frequently used reagents. (Hopefully, Amato will restock the 2006 soon for those people who do not want to ahead and get the 2006C.)
Re: Changing over to BBB's
The B-B-B method is really a simplified, yet more accurate and effective means of maintaining your pool. It's also flat-out easier, cheaper, and less time-consuming. The only down side is all the pool stores and pool service guys lose income! :)
Here's a short-cut to figure out how much bleach you need: I call it the rule of thumb.
1 gallon of bleach (or liquid chlorine) will add EXACTLY its concentration in PPM to 10,000 gallons. So 1 gallon of 6% will add 6ppm to 10,000 gallons. 1 gallon of 5.25% will add 5.25ppm, and 1 gallon of 12.5% LC will add....12.5ppm.
If you double the amount of water to 20,000 gallons, you need 2 gallons to get the same effect.
Therefore, to raise YOUR pool by 6ppm, you'd need 1 gallon of 6% for the 10,000 gallons, and 1/2 gallon of 6% for the 5,000 gallons, or 1.5 gallons to get 6ppm. Since 1 gallon is 2/3 of 1.5 gallons, and 4 is 2/3 of 6, one gallon of 6% gives you 4ppm. Got it?
1 gal of anything adds its percentage as PPM to 10,000 gallons. (works for liters, too, but only if you measure both the bleach and pool in liters).
Carl