New Pool very hard water...

rweiler994

Well-known member
Mar 27, 2021
154
Holts Summit, Missouri
Pool Size
10500
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
Pentair iChlor 30
Getting a new pool this year and have always had a problem due to the local water is sourced mainly from wells with CH and I think from reading (maybe the wrong sites as it was not here) causing my Ph to go up. I do know that with my old Intex pool SWG I had to clear the build up of scale on the SWG nodes almost monthly. I asked the company that installed my softener, and they do not recommend filling a 12000 gallon pool without bypassing the softener, so what I have been doing with my old 8000 gallon pool is running it 6 hour on 6 hours off etc. to ease the load on my softener. Any recommendations of how to control this so I can add muriatic acid less often? I am not sure what it works out to as PPM etc. but 3 different companies tested out water for softener quotes at 26 grains of hardness, so I am pretty sure my high CH is mostly supply water.

Thanks in advance for ideas.
 
what a great opportunity to find out exactly what you have :)

Grab one of the recommended test kits and when you receive it do the following tests on your tap water and if you have water not from your softener..

Test Kits Compared
Recommended Levels

You only need to test

FC
PH
TA
CH

Your PH rise was from a high TA, the scale was from the CH but probably because of the high PH, we can figure this out... (y)
 
I just ordered a Taylor 2006 +salt kit, but will test the softened water when I get it, but all faucets (even outside) run same water, so will have to test the bypassed water later.
 
My Softener is a Kinetico, and the installer saw my 18' pool and asked if I was going to use the softener to fill it. He recommended against it since it would not really be able to complete the refresh cycle in time, so I tend to do shifts as I said, inline and bypassed.
 
I think you did the right thing to fill your pool with a mixture of softener and non-softener water. You can monitor when your water softener will go into recycle mode (or manually do it). It appears that your outside tap is connected to the water softener thus all your fill water (due to evaporation or splash out) will be with softened water which is good that you are not continuing to add high calcium water.
Do you have a tap on your inlet pipe of your water softener? I do, so I can take a direct sample there. If not, then you will have to go on bypass and let the system clear all the softened water to get an accurate reading on the supplied hard water.
Good Luck.
 
If you get your water from the Callaway County Water District, they report the water is 18 gpg. That is hard, but not crazy. About 300 ppm CH I suspect. You should have no issues maintaining your pool without scale. Especially since you get rain to fill it due to evaporation, most of the time.
 

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That is fine. You will need reagent refill for the FAS-DPD and CYA tests early in the summer.
 
rweller994, I had a new pool built in Las Vegas back in 2018. Very hard water, but not as hard as yours. I filled my pool with regular tap (non-softened) water. I had the autofill hooked up into the water softener (actually, the first plumber screwed that up and I still had hard water refilling my pool for a few months until I caught it and had a good plumber fix the problem.).
By the time I caught that I had hard water on my autofill, my CH was 420 in very late 2018. My CH today is ~400. The soft water in the autofill has allowed the CH to stay stable and the small decrease in CH is due to water splashed out from the pool etc.

DO NOT, I repeat, DO NOT put softened water into your newly constructed pool. Just use the tap water with 300ppm CH. This is important because your pool will be curing and if your water is low on CH, the water will leach out calcium from the pool liner (there are a ton of articles warning of the dangers of low CH in pools). 300 CH is in normal range for maintaining pool water and should not be a problem.
What you will want to do is have softened water refill your pool once it's filled and at 300CH+/-. That will keep your CH at ~300.
If, after your pool has cured, you find the CH too high, you can do a partial drain and refill with soft water to quickly lower the CH.

I will also warn you that some pool builders will void their warranty if they find out that you are putting soft water into the pool. It is because they're concerned about low CH For this reason, I wouldn't mention to the builder that you will have soft water on the autofill unless he expresses concern about high CH in the water.
 
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400 TA, wow... going to be lowering that for awhile... :)

I'm seeing a whole lot of
1) lower pH and TA with muriatic acid
2) raise pH with aeration
3) back to step 1 until TA is in normal range
in his future. That should take days if not weeks to get the TA down to normal range.

rweller994, if you opt to add borates to your pool, I highly recommend you use borax rather than boric acid. The end result is the same - they both turn into borates in your pool. The difference is that boric acid will lower your pH slightly, while borax will raise your pH and require additional muriatic acid. And since you're going to need to raise your pH in order to add muriatic acid, borax will help you raise pH faster.
 
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I have seen a lot on Aeration to raise PH without increasing TA I have a small air compressor, thinking of buying a cheap air line and punching holes in it for lots of small bubbles, or looking into a fountain on the return. Either way I know it will not be fast, but as long as I monitor Ph we can swim in it, correct?
 

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