Or a Emperor 400 along with some floaters to keep nitrates low. You can mod the cartridges by removing the carbon, and slipping a rite size sleeve over them. The grey cartridges can be filled with filter floss or polishing pads.
Or an Aquaclear 70. Those are low maintenance, just take out the sponge and wash it with dechlorinated water. Do it weekly or biweekly and it shouldn't ever clog on you. Also, you can just dump a bag of biomax or bio balls in that fugger and you are good to go.
Bare bottoms will also work well in keeping maintenance down. Then you see the poop and vacuum it out when you are water changing. An even easier way is to run a power head on it so all the poop collects in a corner and you just vac that corner.
Since it needs a heater, why don't you just set up a coldwater and be done with it? If you are into them, you could get two fancy goldfish.
Or if you do get a heater, you could just do whatever you want to stock that is suitable. Some species will need sand or gravel, but most won't because quite a few of the species that supposedly do get raised in bare bottoms anyways. Plus, bare bottoms will be easier on maintenance like I said earlier.
Look online how to make an algae scrubber. That will also help in maintaining the nitrate level.
Best of luck, - Raymond