Solar cover and high FC

[grivera]

My SWCG (Aquapure 1400) was originally set at 50% with no cover and kept the FC at about 5. Once things began to cool down at night (55 degrees), the FC got to about 11. I set the SWCG to 40% and then turned on my heatpump and put on a solar cover which has been on fro about 4 days. My water temp is 82 during the day. After the solar cover was put on, the FC kept climbing to yesterdays number of about 16. I have turned the SWCG to 29%. Is this normal? Should I just turn the SWCG off? I'm concerned about getting algea if I have it off with the cover but I also don't want to ruin my pool equipment with this high chlorine--am I at risk here? Should I just remove the cover during the day?

The rest of my nummbers are as follows:

CYA 55
TA 90
CH 220
PH 7.5
Salt 3400 ppm
Pump runs about 9 hours per day.

 

[JasonLion]

You need to turn the SWG percentage down more. You need to adjust the percentage reguarly to keep about the right amount of chlorine in the pool. Using a cover dramatically reduces the chlorine demand, so a simiarly large adjustment in the percentage is to be expected.

 

[grivera]

Thanks Jason, I turned the SWG down to 19%. At which point in FC level do I begin to damage equipment (pump internals, solar cover, etc.)?

 

[JasonLion]

It is a function of your CYA level, somewhere around double the standard shock level there might be some long term risk to a vinyl liner. Around perhaps four times the standard shock level you might start to have some long term troubles with metals.

 

[grivera]

What is the standard shock level for FC?

 

[JasonLion]

The chlorine level required to keep the pool sanitary and to kill alage varies depending on the CYA level, see this chart or my Pool Calculator (see the link in my signature).

 

[JCJR]

Most people report less chlorine usage when the cover is on. It could be that you are adding the same amount of chlorine but are using less so it builds up. Lower your SWG percentage and monitor the CL level.