..... though Im not sure what Im going to put in it yet. There is about 1/2 inch of gravel substrate, a heater, and a water pump that cycles 130gph. Im thinking about buying a new filter for my oscar tank and moving the established filter into the tank. Any fish suggestions? Ive been thinking guppies as theyre easy to breed and I can use them as 'snacks' for my oscar. I dont plan on doing much else with this little tank and want as little hassle as possible..

well just to add one of my favorite fish, a crayfish would look nice in there idk if 20 is the right size though and i saw some at petco even though there not on the website. But if your not gona do the guppy thing you could probly do a pretty good lookn community tank.