I agree with the pygmy suggestion. My cories are ones that never grew in the 55 gallon tank I had even though they had plenty of various foods. A friend of mine also got a few from the same batch and their's never grew much either so I think mine are just small because of genetics or whoever the breeder was didn't provide much care. One has a nuerological disorder (I think he goes into seizures because he starts running into objects almost blindly for 30 seconds at a time every few weeks) and had problems getting to the top of the 55 gallon tank for air (as cories often do). This is why I have my "regular" cories in the 5 gallon. But I would suggest pygmy or panda cories for everyone else.