ok i recently set up a 30 gallon aquarium. it contains 4 neon tetras, 2 black tetras, 1(soon to be) lemon tetra(s) and 2 platy's. i want add cory's to the mix but i cant decide between bronze and nanus cories? which are easier to keep and require what kinda foods? :help: also i want to add 3-4 guppies to the mix or would that be to much? i'd add a betta but i hear there aggressive to these kinds a fish.