Pvc heat exchanger for tank heating?

[CK00020]

I know you can buy titanium heat exchangers, but I am afraid it will degrade or leach so I may try building a pvc heat exchanger out of 2 or 3” then putting a 3/4 inch through it and trying to heat my tank off of my high efficiency boiler. Has anybody done this, any drawbacks, I would still use my current heating system as a backup.

 

[theMeat]

There’s a few companies that make em, like “calorplast “. Maybe get you onto some info to diy. There’s also some threads on it on interwebz.
With my tank (about 300g total volume) and my about 70 deg room temp, with it running (pumps, uv, etc) it settles in around 77 deg. I use electric heater to get it around 78.5.
Think for most tanks, in a home with climate control, this route not much of a savings. Is your situation unique in some way?

 

[ca1ore]

You’d have to search, but I recall some folks using coils of PEX.

 

[CK00020]

I have read some of the threads with the coils of pex in a Rubbermaid tub, I don’t have the space for that, wouldn’t it work the same way? I have 2 300 watt heaters and it seems like they run all the time, year round.
I guess I never ran the tank without a heater on it but my guess is that it would run close to 67, my mixing station is next to my sump and the water in there is like 65. So you are only heating the water one degree and I am heating it 11-12 degrees, this is why I am looking into this option. Also my fish room is in the mechanical room so the boiler is like 10’ away, so piping would be easy.

 

[CK00020]

Also thanks for the tip on the calorplast heat exchangers, that’s exactly what I am talking about.