I have a 10k fiberglass pool and live in N Florida. A month ago it was perfectly balanced with all iron staining removed in December. The entire Spring setting my salt cell to 15% kept my FC at the right level. I went out of town for 3 weeks and asked a neighbor, pool owner, to check it. Long story short, I returned to Ph 7.0, FC 0.5 and the start of algae. Upon returning, I quickly got the Ph back to 7.6-7.7, the FC to 4.5-5. The algae was gone 2 days later and since then it's been 2 weeks of rain and clouds with temps in the low 80s.
The problem is that if I set my SWG at 50% or below (which should be very high based on 2 years of using it), my FC drops as much as 1ppm in 1-2 days with almost no sun. Yes, the rain dilutes things but based on how much I've had to drain, that's not the reason. Alkalinity is 65, CA 230 (due to rain, need to add) and CYA dropped to 45 (because of the rain, need to add). But the lower CYA can't be the reason my FC drops like that with the SWG running at 50%. I need to bump it to 75% just to start seeing small increases. The SWG, an AquaRite 940 is less than 2 years old and I cleaned it when I got back with muriatic acid using the base. There was a bit of build-up but not enough to make it stop producing while I was away and lead to these problems now.
Does anyone have any ideas? Could it be the SWG slowing down like that? There's no algae, everything is clean. And we've barely had any sun for 2 weeks. Thank you!!!
PS oh, and for bonus points, upon returning and finding my pool out of balance, one side had a brown film which goes away with vitamin c -> so it allowed the iron staining I had fought off in December to come back. But I can't easily do anything about that until the weather cools down and I can take care of business after lowering the FC.
The problem is that if I set my SWG at 50% or below (which should be very high based on 2 years of using it), my FC drops as much as 1ppm in 1-2 days with almost no sun. Yes, the rain dilutes things but based on how much I've had to drain, that's not the reason. Alkalinity is 65, CA 230 (due to rain, need to add) and CYA dropped to 45 (because of the rain, need to add). But the lower CYA can't be the reason my FC drops like that with the SWG running at 50%. I need to bump it to 75% just to start seeing small increases. The SWG, an AquaRite 940 is less than 2 years old and I cleaned it when I got back with muriatic acid using the base. There was a bit of build-up but not enough to make it stop producing while I was away and lead to these problems now.
Does anyone have any ideas? Could it be the SWG slowing down like that? There's no algae, everything is clean. And we've barely had any sun for 2 weeks. Thank you!!!
PS oh, and for bonus points, upon returning and finding my pool out of balance, one side had a brown film which goes away with vitamin c -> so it allowed the iron staining I had fought off in December to come back. But I can't easily do anything about that until the weather cools down and I can take care of business after lowering the FC.
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