I use 3M scotch-brite as filters Dred because I also have long haired shedding animals in the house.
A oscar and a chiclid. Anything else?
That's an old picture, I had an Oscar, a Green Terror, a Jack Dempsey, two large Pacu (left side in back behind & below the Oscar), a large Plecostamus & an African Cichlid someone gave me (took it as a rescue).
I had an experiment going with an external filter idea & I had a hose burst on me draining the tank while I was gone to work & killed all but the two pacu, the Oscar & the Pleco.
The Pacu subsequently went on a tear one day & ate the glass thermometer off the side of the tank & the foot long Pleco. So now all I have in there are the two Pacu & the Oscar. The Pacu are both about 21" long & the Oscar is around 13"
What about filtration ?? Fish tank water isn't exactly clean and small bore tubing in the cooling block would easily block with fish crap. ??
Nah; I could remove the water post filtration instead of pre-filtration, I would only have to worry about bacteria & algae build-up & that would take quite some time if I exposed the water to a U.V. light source. Still not a real good idea as the bacteria would eventually build up to a point where it would need cleaned out. The other downside is the water would be much more conductive than distilled water would be & if I sprung a leak it could ruin PC parts.
Roscoroo had some good points, putting the radiator in the large tank & using distilled water & water wetter inparticular. As long as I didn't form a leak & poison my fish it'd be cool.