Freshwater
Bettas - male and female
Guppies
Sailfin Mollies (all wiped out, need to restock)
Mosquito Fish
Dwarf Livebearers
Tiger Barbs - normal, green, & albino
Cherry Barbs
Chinese Algae Eaters (traded in when they got bigger)
Colombian Shark Catfish (bad idea)
Pictus Catfish
Senegal Bichir
Three-Spot Gourami
Green-Spotted Puffer (2 attempts, both failed)
Dwarf Puffers
Cherry-fin Loach
Kuhli Loaches - normal and black
Dojo Loaches - normal and golden
Sumo Loach
Nemacheilus Sp. Loaches (not sure of exact species)
Horseface Loach
Bumblebee Gobies
Stiphodon Gobies
Swamp Darters
American Flagfish
Kribensis Cichlid
Buffalohead Cichlid
German Blue Ram Cichlid
Otocinclus
Sunfish (unknown species)
Large Mouth Bass (bad idea, was a fry netted with other fish, didn't survive)
Canaliculata Apple Snail (may be a related species)
Ramshorn Snails
Bladder Snails
Ghost Shrimp (various species - SW and FW)
various crayfish
Dwarf Crayfish
Saltwater
various Damsels (bad idea)
Checkered Puffer (bad idea, didn't work)
Chromis - green and yellow
Valentini Toby
Hawaiian Spotted Toby
Falco Hawkfish (died for unknown reasons)
Long-nosed Hawkfish
Engineer Gobies
Bar Gobies
Frillfin Gobies
Crested Gobies
Percula Clownfish
Ocellaris Clownfish
Rock Blenny
Starry Blenny
Nerite Snails
various hermit crabs
Stone Crab (removed)
Nassarius Snails
Pistol Shrimp
Probably more in there I'm forgetting about...