I know I'll probably get some pretty strong opinions on this one, but I searched the forums and couldn't find an answer. My husband has this idea that it would be fun to technically NOT close our AG 16x32; rather, we'd keep our automatic cover closed, keep the heater set above freezing (maybe 40-45 degrees), and then fire up the heater for a few fun times (like New year's eve and my daughters' birthdays in February!) when we could swim in warm water with the snow outside. Kinda like a really big hot tub.

A few facts: our pool is sunk into the ground about 24 inches at one end and about 12 inches at the other; backfilled with Doughboy-recommended slurry (a lower psi-concrete); surrounded by a composite deck with 'closed' stairs that go to ground level; sand filter; super-pump; and rheem 333kbtu heater. Use BBB (but actually have only used bleach, not the other two b's.) We live near Chicago. We are having an Aquamatic automatic cover installed tomorrow -- cost as much as the pool, but we decided it would be worth it for safety, convenience, and environmental savings.

I'm guessing that we might be ok, if we are willing to pay for the gas! On the other hand, if we will wind up with all kinds of (expensive) freeze damage, we certainly don't want to do this.

Finally, if we don't 'close' the pool, would it help keep heat costs down if we wrapped the 2" flexible PVC pipes that are above ground but under the deck and installed rigid foam as an insulating layer on the outside of the pool walls (kind of between the uprights). Would that insulating layer help anyway during the regular pool season to keep heating costs down?

Ok -- I'm ready! Fire away with your answers!