Hydropool.com features a wide selection of swimming pool heaters which are suitable for all in-ground and above-ground pools. Shop natural gas and propane heaters in all sizes between 175,000 BTU's and 400,000 BTU's. With a wide name-brand selection from Pentair, Sta-Rite, Jandy, and Hayward, you are guaranteed to find the heater that is right for you.