A few weeks ago, my pool started collecting greenish powder on the bottom.
It did NOT climb up on the sides.
It felt neither spongy nor slimy, I couldn't feel anything at all when I tried to rub it between my fingers.
My pool is covered under a screen (don't know whether that's supposed to help keep pollen out).
It started right after I slacked for a day and didn't measure my chlorine level right when most of the trichlor tablets I was using to raise my CYA dissolved. The FC reading was definitely too low that one day--bad, but not zero: I think maybe 0.5 or 1.0?
SLAMed the pool and the next morning it met all three criteria for doneness.
Later the same week the wicked stuff started coming back. The lowest my FC was at any point after I SLAMmed the first time was 3.5. Thinking it was probably pollen, I put on a skimmer sock, ran the pump a lot more, and vacuumed and brushed frequently.
None of this helped much.
I put some of the greenish stuff in a mason jar with pool water and left it outside. Someone suggested this in another thread a few years back to test for algae vs. pollen. The jar remained clear.
Eventually, the water started to get cloudy, to the point where I could not even see the drain on the bottom very well. So last weekend I started SLAMming the pool once again. Once again, it quickly passed the the CC and OLCT criteria of the three pronged test, but the water was not clear, so I continued to SLAM.
Since I worked long hours and the filter is a hassle, and pressure gauge was reading at clean levels, I never cleaned the filter until Wednesday. When I did, it was REALLY green. Within a day or so after I cleaned it, the pool water once again became crystal clear and sparkly, but by this time the CC had drifted up, and now the completion test fails based on the CC reading. CC is currently 1.5, yet the OCLT test passes with flying colors!
What's more, although the water itself is still beautifully clear (at least so far), the crud on the bottom that started this whole thing in the first place has returned!
The start of SLAM test kit results are as follows:
FC 3.5
CC 0.5
pH 7.3
CH 200
TA 130
CYA 30
I am stumped as to what is going on. If I were just too impatient, I would guess that the CC value would stall for awhile instead of actually increasing while I was still SLAMming, wouldn't it? What IS the crud on the bottom? It can range from greenish to brownish. Could it be organic matter that continues to enter the pool impacting chlorine demand reflected in the elevated CC reading? If so, will I ever be able to stop SLAMming? The chlorine cost is no problem, but I cringe to think of my electric bill after running the pump 24/7 for a few weeks. Or is there a hidden source causing the high CC readings? If it's useful information, my CC measurement has NEVER been 0. It's always 0.5 when things are OK.
Any insights as to what could be causing my problems and how to fix things?
It did NOT climb up on the sides.
It felt neither spongy nor slimy, I couldn't feel anything at all when I tried to rub it between my fingers.
My pool is covered under a screen (don't know whether that's supposed to help keep pollen out).
It started right after I slacked for a day and didn't measure my chlorine level right when most of the trichlor tablets I was using to raise my CYA dissolved. The FC reading was definitely too low that one day--bad, but not zero: I think maybe 0.5 or 1.0?
SLAMed the pool and the next morning it met all three criteria for doneness.
Later the same week the wicked stuff started coming back. The lowest my FC was at any point after I SLAMmed the first time was 3.5. Thinking it was probably pollen, I put on a skimmer sock, ran the pump a lot more, and vacuumed and brushed frequently.
None of this helped much.
I put some of the greenish stuff in a mason jar with pool water and left it outside. Someone suggested this in another thread a few years back to test for algae vs. pollen. The jar remained clear.
Eventually, the water started to get cloudy, to the point where I could not even see the drain on the bottom very well. So last weekend I started SLAMming the pool once again. Once again, it quickly passed the the CC and OLCT criteria of the three pronged test, but the water was not clear, so I continued to SLAM.
Since I worked long hours and the filter is a hassle, and pressure gauge was reading at clean levels, I never cleaned the filter until Wednesday. When I did, it was REALLY green. Within a day or so after I cleaned it, the pool water once again became crystal clear and sparkly, but by this time the CC had drifted up, and now the completion test fails based on the CC reading. CC is currently 1.5, yet the OCLT test passes with flying colors!
What's more, although the water itself is still beautifully clear (at least so far), the crud on the bottom that started this whole thing in the first place has returned!
The start of SLAM test kit results are as follows:
FC 3.5
CC 0.5
pH 7.3
CH 200
TA 130
CYA 30
I am stumped as to what is going on. If I were just too impatient, I would guess that the CC value would stall for awhile instead of actually increasing while I was still SLAMming, wouldn't it? What IS the crud on the bottom? It can range from greenish to brownish. Could it be organic matter that continues to enter the pool impacting chlorine demand reflected in the elevated CC reading? If so, will I ever be able to stop SLAMming? The chlorine cost is no problem, but I cringe to think of my electric bill after running the pump 24/7 for a few weeks. Or is there a hidden source causing the high CC readings? If it's useful information, my CC measurement has NEVER been 0. It's always 0.5 when things are OK.
Any insights as to what could be causing my problems and how to fix things?
I would say it is 1, or maybe even a little less, now, although part of my problem is that I am not too confident of the accuracy of my sub-1 PPM measurements, since the TF-100 test kit has a resolution of 0.5 PPM per drop, and sometimes it's hard to discriminate between a slight tinge of pink and none at all (twice, when determining CC!).