I don't have any gravel in the tank, cuz they could swallow it. I have big river rocks in the bottom, but setup so that they cannot crush the frigs and the frogs cannot get under them. I use tubifex, but when I was feeding them some other stuff, the tank got REALLY dirty. I do not like to have a filter in with these guys, since they are really sensntive to motion in the water and it can stress them out, so I clean the tank weekly.
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2.1 Ball pythons: Goblin, Nothing, and Bela
1.0 Boa Constrictor Imperator: Apache
0.1 albino Cranwell's horned frog: Bene
1.0 Tiger salamander: Slasher
1.0 black kittycat, Inky
A bunch of Oscar cichlids, one giant pleco, huge breeding lot of "fancy" (read: deformed) goldfish, and me an' the boyfriend.