Filterless aquarium stocking?

I have a 10 gallon that I want to use with only an airstone and live plants to get rid of ammonia and other fish waste. I understand that this will lower the stocking capacity of the tank. However, I don't want to use a heater either so I can't keep bettas. My options are guppies, white clouds, or rosy red minnows. What do you suggest? Anything else I should consider?