How to equate 10% liquid chlorine to pounds of chlorine?

Longtown

Member
Apr 2, 2018
11
Carlton Landing, Oklahoma
I have a new commercial pool that has three Hayward 940s that has to be constantly supplemented with liquid chlorine.
I know the 940s produce 1.4 lbs of chlorine per day and I know how much liquid 10% chlorine required per day. If I knew how to correlate the 10% liquid to pounds of chlorine I could make a better decision as to which commercial SWG I need. I know the Hayward C6 makes 6 lbs per day for instance.
These commercial units are very expensive and it’s important to get this right this time....no more trusting the pool builder!
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
34,629
Laughlin, NV
You can use Poolmath. Just determine how much FC you are adding each day with LC, then back into the lbs of chlorine that equates to .
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
17,530
Tucson, AZ
Pool Size
16000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
13 fluid ounces of 10% LC in 10,000 gallons of water will raise the FC by 1ppm.

3 x 1.4 lbs of chlorine gas output in 10,000 gallons of pool water will raise the FC by 50.4ppm.

So the 24 hour output of the SWGs is equivalent to 5.1 gallons of 10% LC .... theoretically speaking. YMMV
 

JamesW

TFP Expert
Mar 2, 2011
22,029
Are the cells being run at 100% x 24/7?

What is the volume of the pool?

How much liquid chlorine are you adding per day?

What is the bather load per day?
 

Longtown

Member
Apr 2, 2018
11
Carlton Landing, Oklahoma
Are the cells being run at 100% x 24/7?

What is the volume of the pool?

How much liquid chlorine are you adding per day?

What is the bather load per day?
on the weekends we add 6 gallons 10% per day in addition to the three SWG's each producing 1.4 lbs. SWG's are on 100% 24/7

The bather load is 128 pool is 40000 gal.
 
Last edited by a moderator:

JamesW

TFP Expert
Mar 2, 2011
22,029
Is the 128 just on the weekends?

What levels are you getting for CC?

6 gallons of 10% will raise the FC by 15 ppm. That’s the equivalent of 5 lbs of chlorine gas.

The 3 SWGs will provide about 13 ppm from 4.35 lbs chlorine gas.

So, your total demand is about 9.35 lbs chlorine gas.
 
Last edited:
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