First of all: thanks everyone!
I thought I'd try:
Breeding White clouds and Hillstream loaches in a 20 gal
Rearing fry and breeding shrimp and snails in a 15 gal
Clown Killis, ricefish, and least killifish/endlers in a 20 gal.
Taking Cherry Barbs, Marbled Corys, neon tetras, and fancy guppies shall be kept in my 63 gallon and brought out to breed in a 5 gal aquarium.
Any thoughts?