So I’ve run into a dilemma... my TSNxRTC catfish grew quicker than expected and needs a bigger home within the next month. I have a 1300 gallon pond but we’re coming to the coldest part of winter and the pond gets down to about 45 Degrees Fahrenheit at night. So I’ve been trying to think of ways that I could heat the pond. Then I came across the idea of building a compost bin and running copper tubing all throughout the bottom of it and pumping water through it. My question is does anybody know how effective this would be? Any ideas on how much copper tubing and what the flow rate of my pump should be? Any other ideas for how I could heat my pond naturally?