Did I learn something new this year? It started with overshooting my cya level goal in the Spring. My test back in May after adding stabilizer and an extra week of mixing was 60. I began keeping a higher-than-ever fc level in my pool. I dose with LC, aka bleach, daily. From the previous six years history, I know that the chlorine demand will start out at about 1 and work it's way up to 2 1/2 ppm for my pool beginning its peak in late June until mid August and work it's way back down.
This year, however, I got thrown for a loop. Beginning mid July, I started losing 4 ppm per day. I first thought it to be stale KIK brand 10% bleach (I like to call all sodium hypochlorite bleach); but that tested out okay. Late July, I restested cya and it was still at 60. I then became convinced it was organics of some sort but passed all three SLAM-passing criteria even before starting. Started to SLAM in late July when I got a cc reading of 1 on a test; but got interrupted and never got to go beyond one adjustment.
In early August, I tested cya and it showed 50. I had been trying to keep fc between 7-11 due to my fear of some sort of organic.
Since I suspected some sort of weird organic, I was keeping fc way up there; maybe 8-10 most times, but would regularly get a test result down around 6-7 before dosing due to excessive fc loss.
In early August, right after my cya test, I conducted SLAM. I had to add chlorine twice during the day; once had to add 6 ppm and the other time, only 3, but the nightime test for OCLT came out to be 23 and the morning result at 22; I passed and ended SLAM. But the next evening, I had gone from 22 to 10 and it was a cloudy day. Excessive chlorine demand continued.
I started following threads of SLAMs. Mknauss was helping someone who was passing OCLT but having larger-than-expected daytime loss in fc. He suggested that the cya may be actually lower than the test result causing higher-than-expected loss.
I had just recently recently rechecked my cya. Friday, it showed 35 (40). Over the weekend, I've got my fc down to 5-7 targets, and suddenly, my fc seems to be losing it's normal loss of 1 1/2 to 2 ppm daily for this time of year. So is it possible that, from the time when I first started experiencing extra fc demand until now, that a combination of trying to keep fc a little higher, along with an overestimated cya level; I was actually experiencing more chlorine use due to more uv loss by trying to keep it above "goal" levels for the actual cya level and it was never organics?
This year, however, I got thrown for a loop. Beginning mid July, I started losing 4 ppm per day. I first thought it to be stale KIK brand 10% bleach (I like to call all sodium hypochlorite bleach); but that tested out okay. Late July, I restested cya and it was still at 60. I then became convinced it was organics of some sort but passed all three SLAM-passing criteria even before starting. Started to SLAM in late July when I got a cc reading of 1 on a test; but got interrupted and never got to go beyond one adjustment.
In early August, I tested cya and it showed 50. I had been trying to keep fc between 7-11 due to my fear of some sort of organic.
Since I suspected some sort of weird organic, I was keeping fc way up there; maybe 8-10 most times, but would regularly get a test result down around 6-7 before dosing due to excessive fc loss.
In early August, right after my cya test, I conducted SLAM. I had to add chlorine twice during the day; once had to add 6 ppm and the other time, only 3, but the nightime test for OCLT came out to be 23 and the morning result at 22; I passed and ended SLAM. But the next evening, I had gone from 22 to 10 and it was a cloudy day. Excessive chlorine demand continued.
I started following threads of SLAMs. Mknauss was helping someone who was passing OCLT but having larger-than-expected daytime loss in fc. He suggested that the cya may be actually lower than the test result causing higher-than-expected loss.
I had just recently recently rechecked my cya. Friday, it showed 35 (40). Over the weekend, I've got my fc down to 5-7 targets, and suddenly, my fc seems to be losing it's normal loss of 1 1/2 to 2 ppm daily for this time of year. So is it possible that, from the time when I first started experiencing extra fc demand until now, that a combination of trying to keep fc a little higher, along with an overestimated cya level; I was actually experiencing more chlorine use due to more uv loss by trying to keep it above "goal" levels for the actual cya level and it was never organics?
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