Bill Stock wrote:

wrote in message
...
Personally, I'd concentrate on keeping the UGF fed with oxygen as a
priority
over the heating (unless you live in a very cold place). Oxygen starvation
snip
Thanks Mark the Powerheads on the UGF don't draw much current, so they I
have them on there now. The temp does get down to the low 50s during the
winter months, hence the concern about the heaters. I guess the tank should
hold it's temp for a while though, even at 50?F.

I'd wonder if I'd insulated the tanks as well as possible, first.
Stick 1" of polystyrene on the back and sides, and bottom if not visible,
to form a backdrop, and keep it warmer.
Depending on the design, insulating the top may also be possible.