Chlorine Usage Spiked

[QingGuy]

FC 5
CC 0
pH 7.2 (I hit with MA yesterday to bring TA down, it was at 90, typically keep this at 7.6)
TA 70
CH 400
CYA 50
CSI -.39

Been a while since I've been on here. Probably a good thing when it comes to pool chemistry.

I use liquid chlorine, and I usually go through about 2 - 2.5 ppm per day of FC. I'm now using 4-5 ppm per day. I'll typically add 56 oz of 10% daily which tops me off at 5 ppm. Yesterday morning when I tested when I tested I was at 0 ppm FC. I added 142 oz of LC, tested about 45 minutes later, and I was at 5 ppm. I tested at 8:30 p.m. (no sun), and I was at 1 ppm FC. I tested this a.m. before sunrise, and I was at .5 ppm FC. Added 128 oz of LC which took me back up to 5 ppm. This has been going on for about 4 days.

The pool is crystal clear. I've inspected it for algae and cannot see any. I was in the pool on Saturday and didn't see any either.

I've been running this way since I switched to LC at the beginning of the 2023 pool season without any issues. Any ideas what's going on? Typical Vegas sun... actually it's been cooler than earlier this summer when we had many days at 115 or higher.

Any thoughts? I'm thinking about kicking my CYA up a bit to say 60.

 

[mknauss]

When was the last time you tested CYA? When our water temperature is 90F and the intense UV from June/July the CYA gets degraded pretty quickly.

Always can do a proper OCLT. Need to get FC to at least 10% of CYA at the start of the test.

 

[QingGuy]

When was the last time you tested CYA? When our water temperature is 90F and the intense UV from June/July the CYA gets degraded pretty quickly.

Always can do a proper OCLT. Need to get FC to at least 10% of CYA at the start of the test.

I tested CYA yesterday. Just noticed I omitted that in my numbers. Updated.

Yeah, after I went to bed last night, I thought about the 10% thing. I could do that tonight.