pH trending higher

[BoHpool]

I have started using a DIY LC feeder in our big pool. It is working well I am just trying to find the right setting to keep my FC above 5 during the daylight hours. My chemistry is, CYA 50, TA 110, CH 330. My pH was rock-steady at 7.8 until I started using my feeder setup. Now it is trying to stay at 8 maybe 8+. Is there something going on that I am missing? I did an OCLT Saturday night into Sunday morning. I did not see any loss overnight.

 

[Sunnydaze]

Were you using tabs prior to going to liquid chlorine?

Ph will to rise on it's own until it reaches its happy point. Lowering the TA to 70 should help slow the rise.

 

[BoHpool]

Yes, we were using tabs. For a month or so I was using tabs and adding LC. I was trying to raise the CYA and use up the last of the tabs. I do plan on letting the TA trend down.

 

[Sunnydaze]

Yes, we were using tabs. For a month or so I was using tabs and adding LC. I was trying to raise the CYA and use up the last of the tabs. I do plan on letting the TA trend down.

The tablets are very acidic. They were constantly lowering your ph. Once you remove regular acid additions from the tabs, the ph will rise naturally. You'll need to control it with muriatic acid. Once ph hits 8, lower it to 7.5-7.6 with muriatic acid.

 

[BoHpool]

Ah, that makes sense. I have been reading the "so you want to use borax" thread. Go have any experience with borax and the pH buffering effect from it?

 

[Bperry]

Ah, that makes sense. I have been reading the "so you want to use borax" thread. Go have any experience with borax and the pH buffering effect from it?

It just slows the rise down a bit but requires the same amount of acid over time. Once your TA gets down that will make a bigger difference than borates.

 

[BoHpool]

It just slows the rise down a bit but requires the same amount of acid over time. Once your TA gets down that will make a bigger difference than borates.

As much acid as I'm using the TA should be down in no time.

 

[wireform]

The way to lower or knock down the TA is by adding MA to bring the PH to the 7.2 territory then aerate the water back up to 8.2ish and do it again. Each subsequent lowering of the PH also drops the TA. Having a TA in the 60-80 range will cause the PH to rise much slower. Then find the PH in the mid to higher 7's which will be the happy spot with little rise.

 

[BoHpool]

So my TA is down to 80 and my pH is staying more steady and around 7.8. Good stuff.