Now I'm ready to take care of my CH problem


Active member
Mar 27, 2017
Leander, Tx
ok, well I have my CYA at 55 and I've stabilized my FC level where I'm keeping between 7-10 for the most part. I had order some calcium chloride to fix my CH problem since it was at 180 and I have a pebble finish pool. I was surprised the CH remained steady at 180 even after replacing quite bit of water. So I tested my tap water and it was reading 120. Out of curiosity I looked up the what the Leander city water report was and it showed 210 Ca/Mg hardness for 2015 the latest report. '10-'14 showed between 165-189. So I guess the numbers probably make sense.

So back to fixing the problem. I ordered a 25lb tub of Calcium Chloride. This is huge, but by my calculations on pool math I need to add the whole thing. To go from 180 -> 300 pool math tells me 352 oz or 22 lbs. The tub says to raise a 20,000 gallon pool 100ppm add 25lbs. So I was going to add half test then add 2nd half test.

1) Am I off on anything I said above?
2) Any special instructions on how to add? It just says to spread across surface. Do I grab a scoop and just start tossing it across the pool?

TIA for any suggestions.


Bronze Supporter
TFP Guide
Jul 24, 2015
Central Valley CA
Your math is correct and you can just spread it across the surface and brush. It does generate heat so brushing is important but you don't have to kill your self just keep brushing till the granules are gone. Don't make the mistake I made and add to much and by to much I mean 300 ppm. I live in a warm climate too and brought the new pool to 350, by the end of the first swim season my CH rose from 350 to 600 due to evaporation. If I were you I would shoot for no higher than 250 and check again in a month or two.

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