Yeah, I was thinking of Alum, but don't know if you can get it in small thin wall tubing like copper. Will have to do some research. I've tried to think of a solution that eliminates the need for the copper to be in contact with the water.Hi Patchworks,
Although aluminum isn't quite as good a conductor as copper, I have not heard of problems with aluminum in water. Another thought might be a "closed system" where the water is only circulated within the tubing.
You gave me an idea. I guess I could coat it in that rubber stuff people use to make grips on tools.. Simply coat it with that stuff before I put it in the PVC!!!Are you making a coil like you see used on woodstoves to make hot water?
You could line the copper pipe with a plastic or pvc hose. Slip it inside. The metal will still conduct the heat but plastic hose with spare you the grief the copper may bring. The double wall might even hold the heat better.
I've thought about running simple tubing in and out of my light before but the idea of more water and electricity together has stopped me. Kids, cats and a not to observant husband made me forget the idea.
I'll look in to this PEX pipe and see if it can help. My project is using my ballasts to heat my tank.I'm not sure what your DIY project is, but you could use PEX pipe. If it's safe for humans to drink, I would assume it is ok in the aquarium. The only part that I know would be a problem is the steel ring that you crimp on the joints are corrosive, so you wouldn't want a joint in the water. If you did have to put a joint in the water, you could seal it in silicone.
Edit: I just saw your project. Ignore PEX, it won't work for that.