Lowering FC

[Kit]

After refilling my spa & balancing the chemistry, I noticed after several days that the FC rose from 6 to 11. I assumed that this was possibly due to several factors:

1. The spa was not being used since the refill,
2. The spa remained covered,
3. The ambient air temperature was around 55F - 60F (down from summer temps of 80F - 92F),
4. The SWG was running at 40% for 4 hours/day (summer settings).

Two days ago I turned off the SWG, but have not noticed any decrease in the FC level. In consideration of the first 3 factors above, I'm thinking that it will take a while for the FC to fall back down to the 5 or 6 level. Is my thinking correct? If so, what would be a guesstimate of the time until the FC falls?

Thank you.

Kit

 

[pooldv]

Chlorine consumption drops considerably with water temp below 70, no swimming and less sun due to shorter days.

 

[Kit]

As I suspected. Actually, the water temp is around 55F - 61F.

 

[pooldv]

Even more below 60. Probably will use around 1-2 ppm per week.

 

[Kit]

Thank you! Much appreciated.

 

[YippeeSkippy]

Keeping the autocover closed extends the FC presence in my pool enormously. I can turn my SWG down and keep it about 10-20% in summer, and barely functioning in winter.

 

[Kit]

Keeping the autocover closed extends the FC presence in my pool enormously. I can turn my SWG down and keep it about 10-20% in summer, and barely functioning in winter.

That has been my experience as well. This will be my first winter with the spa so I expect to make some adjustments with the SWG.