Wondering how much evaporation loss is expected in covered pool?

[otherchuck]

Greetings all!

I know this forum is for "just getting started" and we have had our fiberglass pool since 2006 (thus not really "getting started"), so feel free to direct me to a better forum for this query.

We had leak around the skimmer that we THINK we fixed. We haven't yet refilled the pool above the skimmer leak line, so we haven't really tested the theory that we FIXED it yet. We will refill shortly. But our pool is covered nearly all the time until summer with a tan pool cover. As I said the pool is fiberglass, approx 12'x24', and we live in southern California, USA, where temps are about 70+ degrees fahrenheit now (May), but will be heading to 80's/90's shortly (i.e., summer).

Bearing all that in mind, how much loss should I expect due to evaporation? I want to be able to confirm our leak fix worked, and in order to do that I need to estimate normal evaporation loss. The main issue, I think, is the cover. I have seen estimates of expected evaporation loss, but I have not seen estimates of evaporation loss for small pools that are covered almost all the time.

Thanks for any help here!

Otherchuck

 

[MSchutzer]

Next to nothing. I have my pool covered by a floating solar bubble cover when not in use and I may loose a 1/4” to 3/8” in a couple of weeks in the summer when the water is in the 90’s range.

The cover really does cut down on the evaporation loss, cuts the chlorine consumption to around 1 PPM per day, and keeps the heat loss to a minimum.