Compost Bin Pond Heater


Black Skirt Tetra
Original poster
MFK Member
Nov 28, 2017
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?


MFK Member
Nov 19, 2007
That’s an interesting idea. I’d imagine you’d want to run the flow as slow as possible through as many feet of winding copper coils as possible to maximize heat exchange. You’d also want to make sure you place it after the filter so no debris clogs the pipes. Then you’d want to plug the pump into a Temp controller so you can maintain some control. It would be similar to those solar pool heaters.

Your compost bin would have to be rather large for this to work. I’ve heard of folks building a big box, painting the inside black, running a bunch of copper through it and covering the whole this with a pane of glass to capture as much heat as possible. If you try it, post updates
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Giant Val

MFK Member
Jul 15, 2017
Qld, Australia
A few years ago I heated a 40,000L (10,000 gal) pond with a large compost heap. Compost heap was about 4m diameter and about 2m high. I coiled 300m of 25mm poly pipe inside the heap. I had a pump that circulated 10L/minute of pond water through the pipe and returned it to the pond. It was very effective. The return water was very hot and kept the pond warm through winter. I live in Qld Australia (subtropical) but cold enough for frosts on about 5-10 days each winter. I only used it for one winter, but it easily lasted the four months I wanted it for. In fact when I dismantled the compost heap after about 12 months it was still making heat. I log the water temperature. Without the heater the pond drops to around 13 degrees C in winter mornings. With the heater only got down to 18 degrees.