SWG questions


Platinum Supporter
May 4, 2010
SW Georgia
I am in the process of analyzing SWG's and most, if not all the websites indicated that they can generate enough chlorine in a day to keep your 40k pool sanitized. My question is, what chlorine level are they using and how long is the pump require to run to acheive this level? Is their day an 8 hours or 24 hours? If it takes 24 hours to keep the pool properly sanitized you would need to factor in the electric usage into the economics equation (assuming is does not take 24 hours to cycle your water one time). Most of these sites indicated that their system produces an equivalent number of dry lbs. of chlorine per day (2 to 1.45 lbs. per day). I am currently using BBB (10.5% hypo) to keep my pool sanitary and am working in fluid oz. Is there some way I can convert their dry chlorine lbs. into oz. of 10.5% Hypo so as to compare apples to apples? I run my pump enough hours to cycle the water in my pool one time.


TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
Silver Spring, MD
It varies from manufacturer to manufacturer. Most of the better units are sized assuming the pump is on about 8 hours a day. But there are some off brands that assume the pump is running 24 hours a day when making up their recommended pool size.

It is always best to get a unit designed for a pool larger than you actually have, regardless of the actual pump run time.

When a SWG specific a number of lbs of chlorine per day, they are talking about chlorine gas, not solid chlorine. You can use the Pool Calculator to figure out equivalences, since chlorine gas is an option on the kind of chlorine you are using in the FC section. You will need to fiddle with the target FC level until you get the amount of chlorine gas the unit is speced for, then look at the amount of bleach to see the equivalence.