I got my first tank, a 120 gallon glass tank this spring. (I need wide open spaces, room to make the big mistakes) When I caught the bullhead fry, you could put 5 across your thumbnail. I almost stepped on a parent that was guarding them. Thanks to Aquarium CoOp's easy fry food and brine shrimp and other random fry foods, they grew fast. When they were about 2 inches long a give most of them to someone looking to stock a new pond. So no I don't have a pond, and no I don't sell anything I catch.
Last weekend, we thinned out the tank again. it had 57 yellow perch, 7 sunfish/bluegill/rock bass, 3 baby bullheads and way too many snails and crayfish to count. I kept about 20 perch, which a friend was going to use for bait (I check with the DEC and if they are used in the water they came from, it is OK). I know a teacher that wants the sunfish/etc and some of the others. I also have 5 active adult mudpuppies in the big tank, The teacher will take some of them for her classroom too.
Mudpuppies are amazing to watch swim and wander around. They are big, so you need a big tank.