[TAB]

I think I would look into coolent rather then tank water... Then have another coil that heats the water. JIMO.

 

[TAB]

Tab, Can you give more detail on your thoughts? I'm having a hard time following this idea?

A pic is worth a thousand words... forgive my crapy paint skill.

basicly you have tow closed systems, One tht pumps a "coolent"( Which could be water) from a bucket, around the ballest, then back to bucket. The 2nd pumps water from the tank, into a a coil indside of the 5 gal bucket and back to the tank. That way neither system every contacts each other.

Once agan sorry for the very crapy paint drawing... using a touch pad on a laptop sucks.

 

[TAB]

The only cost effective tubing I can see you using for heat transfer that is safe and won't melt( should the pump fail. the last thing you want its to come home to an empy tank) is Ti pipe which Canot be bet buy hand and costs $$$$.


Copper on the other had is cheap,

 

[TAB]

I don't think that plastic is a very good conductor of heat. I also don't think there is enough dwell time in the fliter to heat the water effectivly. Now if you were get an extra long imput hose and coil it inside of a 5 gal bucket that the "coolent" that would work, but The very long length of pipe would slow down your flow rate alot, which may or may not be a prob.