I used a diy heat exchanger on my reef system years ago. It worked well. I don't think I ever broke even off of it between build cost and lowered electric bill though. It was up and running on my reef the last 5 years I had the reef. You have to build or buy it and still need a source of hot water. That hot water still needs to become hot some how. I used my hot water heater which was natural gas so cheaper then electric but the hot water heater kicked on more then in the past. A nice side effect of doing that way was instant hot water at any faucet in the house. I want to say parts was around $500. Probably a couple weeks of research and design time. Took about 8 hrs to install and get running correctly.
Currently I'm in a house with hydronic heating and I have multiple areas of control one being my fish room. I heat the room to 80°f which keeps the tanks around 76°f. The problem with that is it's so hot in there doing any real manual labor is not all that fun. Also if the tank is well insulated it's temp is lower. Some tanks, closer to the radiators are warmer also.
So
B
Black_Diamond
I was wondering if you would be willing to post about your system? If you have a build thread maybe link to it? Or if you'd be so inclined to make a build thread explaining it and link us to it. I would appreciate it and I'd think
dr exum
would too, probably lots of others also. TIA!