I have an 18' x 33' above ground pool and heat it with a Teledyne Lars oil heater and am extremely happy with it. There are a couple sites online where you can get them. I didn't want the cost of risk of a big propane tank. I ruled out solar and electric because of our location (CT) and the cost. I bought the oil tank locally - it's a lifetime stainless Roth 165 gallon tank that looks like a little house ($750) and well worth the extra money in appearance and ease of use, gauges and so on. The other install involved the local oil company service guys to install the lines from the tank to the heater. The local electrician to install the wiring for the furnace to the electrical box at pool. The local husband (mine) to install a concrete pad for the tank and the local pool guy to hook it all up and get it running which I can now do myself. We put mouse stuff in it over Winter as the mice population can wreak havoc on the wires over Winter. We kept the pool at a silly 89 degrees from April through October here in CT and used 4 full tanks of oil. It was a bit of a guilty pleasure but wonderful.