I'm a guppy breeder, though since I've been buying more horses, I just threw ALL my guppies (I only had about 50-70) into my 55 gallon with 3 bettas (2 males, 1 female. Not a single nip of the tail going on amazingly.. I watch them constantly, they've all been together for a year now. Separating them now since I've brought back a few 10gs.) without any fry food, so my fry have VERY stunted growth. :/
I fed them super crushed and fine flakes, and crab food (Powdery stuff I've used over the years, vet OK'd it LOL) which was VERY bad of me, I feel SOOOO guilty.. But they're very happy, just... small.. LOL. Some actually turned out kinda pretty, no show quality.. They were bred/born in the 55g, so I had swordtails breeding with albinos and grass guppies and cobras.
So now I currently have..
10g with red petstore betta female
10g with solid light chocolate/pineapple (I forget what the coloring's called.. It's basically tan brown.) male betta I purchased from a nonshow breeder, divided into two also holding a solid purple petstore male.
55g holding guppies, and various plants I grow for my turtles. Some guppies are going to be given to friends and what's left moved to a 20g, so the turtles can move to the 55g (It's deep, but it'll have to work because I took these guys in from someone who wasn't taking care of them at ALL.. 1 painted, 3 RES, all youngins, buying a couple 75gs soon.