Loss of water in cold weather

[ralph]

Didn't know where this should go. All of sudden when the temperature dropped below 35F I experienced a sudden loss of water. I do not close the pool (here in North alabama it's not that cold so I leave the pump on). The drop has been 1-1/2 inches (previous norm was ~ 3/8 inches). I would really appreciate any evaluation.

Ralph

[waterbear]

What is the water temperature and the ambient temperature? If the pool is much warmer it is probably evaporation. You can verify this by checking the level of a chemical that stays pretty constant such as CH or ALK. (or CYA if you have a SWCG or use bleach), assuming you have not backwashed and topped off since your last water test. Once you top off the pool to the previous level the chemical level should be the same as your last test. If it has gone down then you might have a leak somewhere and you might want to bucket test.
However, evaporation would be my first guess. Often it can be seen as a mist rising off the surface of the pool, particularly if the pool is heated.

[robbym70]

bumping this thread...

I've got an above ground pool. Before the winter set in I drained water to just below the lower lip of the skimmer. Looking under the cover now in the spring the level is much lower than when I put the cover on...say 12 inches lower or so. I'm filling now with hose water but I'm worried about the water level drop. I did peek my head under a few times during the winter and was suprised at the warmth of the space under the cover. Could the water have evaporated that much. There is no sign of water pooling outside the pool but maybe it's leaking into the sand underneath the liner?

Anyways I'll monitor the level closely going forward but I wanted to throw this out there to the people with more experience than I. This is my second season opening the pool.

Thanks.