I have watched many videos on solar pool heaters. Here is my version. I am a regular dude just getting along in life. Not a scientist or numbers guru. Here is what I found. I used 50 feet of green garden hose, a 1/50th hp Dayton Pump that pumps about 300 gallons per hour that is, Chemical and Heat resistant. 200 feet of 1/2 inch black plastic hose a piece of plywood painted black and plastic tie wraps. In total I spent about $220 for the project. I get a consistant 4 Degree rise in temperature. So if the pool is 76 coming out at the bottom it is 80 degrees at the hose coming out. The initial hit out of the hose when I turn it on is over 120 Degrees F. So as the pool heats up it continually heats 4 Degrees more so as the pool warms it keeps getting warmer. We only get about 6-8 weeks of good pool weather as we are 50 Degrees N latitude. I run it about 5-6 hours a day. The temperature is consistent throughout the entire pool. The heat in our neck of the woods has topped out at about 82-84 degrees F. It is a good supplement heat when used with a Solar Cover. I’m happy with the results and may add another panel for an additional 4 degree rise in temp.