How to either cheaply heat a pool, or heat a pool for one day?

[PoolDoc]

I can accept that.

But I always have to keep in mind that Google sees and remembers all these posts, and that they stick around for years. So, when I or one of the mods, sees a solution that could work for some, but be dangerous or damaging for many, we try to counter-post or add a correction. It's not necessarily for you, or even for the OP, but for the guy that may be reading this 3 years from now!

There are posts here that I've never read -- many of them -- but when we see one, we try to 'fix' it, so that it's reasonably safe, not just for knowledgeable and skilled people, but also for those who aren't

Good luck . . . and I'm glad you found a solution that worked for you.

[CarlD]

Heating a 6000 gallon pool is a tough chore, heating a 15,000 or 20,000 gallon pool quickly is tougher.

The goal is, as Poconos says, to pump BTUs into your water. One BTU is the amount of energy to heat one pound of water 1 degree F.

10,000 gallons is over 85,000 pounds of water. That means you need 85-90,000 BTUs to raise your water 1 degree. You'll need 10-15 times that to get you water just to the mid-70's from the mid-60's

Heaters are rated in BTUs per hour......For one day? I have NO idea how much NG or Propane that would take.

Just my take.

Carl