This is my first pool; I have a rectangle pool, about 18,000 gallons, including the spa. From what I can tell, it's an older system, and the heater is disconnected from the plumbing.
18,000 Gallons, Pool (32' x 14', depth 6' & 4'), Spa (8' x 5', depth 3') is where I came up with the Gallons. I...