Typical Calcium Hardness for Texas pools?


Active member
Aug 27, 2020
san antonio TX
I just had my water tested by Leslie's and they found a calcium level of around 400 ppm. I then went home and retested with my K2006 kit and found a reading of around 600ppm. I've heard that Texas has very hard water but I wasn't sure if either of those numbers were way out of line. If they indeed are, how would I go about reducing my hardness without effecting anything else? My chemistry is very good apart from the hardness. Thanks!


Bronze Supporter
Jul 17, 2019
Prosper, TX (DFW)
Thats at the upper end of where you want to be, but manageable. To reduce calcium, you would have to partially drain and refill. Do you know the CH of your fill water?

You can also add CH from some chlorine products. How are you chlorinating your pool?


Active member
Aug 27, 2020
san antonio TX
Good to know. This is after I drained about 6" off and refilled yesterday to reduce CYA. I don't know specifics of the fill water, sorry. I just took ownership of the house and pool a few days ago and have not administered any chlorine but I do know they were using pucks in a floater. I will be using unstabilized granular or liquid chlorine only when I start to add.

Rancho Cost-a-Lotta

Silver Supporter
Apr 10, 2018
Rancho Cucamonga, CA
You should be able to effectively maintain a pool with a CH level of 800 ppm (or more). CH is only [one] factor in the Calcium Saturation Index of your pool water. High CSI levels are prone to calcium scaling and low levels are prone to plaster etching. CSI should be kept in the range of 0.0 to -0.30 and can best be manipulated by adjustments to TA and pH levels. The article does a much better job of explaining than me, so here you go:
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Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
bk, it's hard to do, but try and "cut the cord" from the pool store. Their testing will only make you second guess yourself. You have a very reliable test kit, so trust in your own testing. If you ever have a question about a result, you can ask us for clarification. TFP also has videos on YouTube for testing. Hopefully you have a speedstir, but if not, I would get one because it really helps with those tests.

So for now, just be sure to monitor the pH closely to compensate for the slightly elevated CH. I don't recall the CH level from the Edwards Aquifer, but also keep an eye on the weather. We've dodged a lot fo storms from the gulf so far, but if one heads our way, that's an idea time for you to lower a lot of water in advance and let Mother Nature fill it back up for free with no CYA or CH. :)


Gold Supporter
Nov 19, 2018
Tuscola, TX
Pffft, 400...that's nothing. ;) Mine has been in the 800s. Will probably do a water swap sometime in the near future as it's been two years since filled. BTW, I have zero calcium build up on the walls or anywhere else.
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Well-known member
Jul 11, 2019
Manteca ca
I'm in the same boat, my CH level is 600ppm. I'm using the Pool Math app to keep my CSI in the acceptable range. My TA is at 60 and my pH is at 7.6 which puts my CSI at -0.06 with a water temp of 68*F.