pH keeps dropping even after using increaser

[Manikshaw]

I’ve added pH increaser twice this week and it still falls back down after a couple of days alkalinity seems fine so I don’t know what’s pulling it down

 

[syedsam]

Sometimes heavy rain can push it down too mine always falls after storms I usually wait a day then adjust instead of chasing it every time.

 

[John Faulkner]

I had the same issue when I was using trichlor tablets they slowly lower pH over time switching to liquid chlorine stopped the constant drop.

 

[George Kelly]

I’ve run into that before, and it can be a bit of a guessing game. Even if alkalinity tests look okay, sometimes it’s on the lower end and doesn’t buffer the pH very well, so it keeps drifting down. Another thing that pushes pH lower is high aeration, if you’ve got waterfalls, spa jets, or even just a lot of splashing, the CO₂ leaving the water makes it drop faster.

What helped me was keeping an eye on both TA and pH together instead of treating them separately, and switching up my chlorine source like John mentioned. Liquid chlorine tends to be more pH-neutral compared to tablets. Once I balanced the TA a little higher and cut back on tablet use, the pH finally held steady instead of sliding down every few days.

 

[Katherine Morgan]

I had the same head-scratcher a while back, and it turned out there were a couple of sneaky things at play. One was filled with water, while mine comes out of the tap slightly acidic, so that every top-off would drag the pH down again. The other was chlorine demand. When the pool was fighting off a lot of organics, the constant dosing seemed to lower the levels faster than usual.

What finally made a difference was testing the source water and treating it before it entered, plus administering a larger shock to get ahead of what was depleting the chlorine. After that, the pH increaser actually stayed in place instead of sliding back down within a couple of days.

 

[Amber Chase]

I’ve had the same struggle, and in my case it turned out the total alkalinity wasn’t quite high enough, even though it looked “okay” on the test. Once I brought TA up a bit more, the pH stopped swinging so much. I also noticed that when I ran water features a lot, the extra aeration made the pH fall faster. Might be worth checking both things together instead of just chasing pH on its own.

 

[Andrew Coleman]

I had that same issue where pH just wouldn’t stay up, and it turned out to be a combo of things. My fill water leaned acidic, so every top-off dragged it down, and I was also using trichlor tabs which kept pushing it lower. Once I tested my source water and switched over to liquid chlorine, the problem pretty much disappeared.

Might be worth checking both the water you’re adding and your chlorine type, sometimes it’s not the increaser at all, but those underlying factors that keep fighting against you.

 

[Henry Graham]

I’ve battled that same problem before, and in my case the culprit wasn’t obvious at first. Even though TA looked “normal,” it wasn’t giving the pH enough stability, so it kept sliding back down. On top of that, I later found out my auto-feeder with tablets was slowly pushing it lower every day.

What finally helped was bumping TA up a touch higher than the bare minimum and cutting back on tablet use in favor of liquid chlorine. Since then, the pH holds steady a lot longer instead of crashing every few days.