I know I do this sort of thing a lot, but, excluding variants, I have kept 92 species of fish as of 8/10/21.
Amatitlania kanna
Amatitlania myrnae
Amatitlania nanolutea
Amatitlania nigrofasciata (since siquia is about to become synonymized with nigrofasciata)
Amatitlania sajica
Amatitlania septemfasciata
Amphilophus labiatus
Amphilophus lyonsi
Amphilophus trimaculatus
Ancistrus cirrhosus
Ancistrus dolichopterus
Apyosemion australe
Ataeniobius toweri
Aulonocara stuartgranti
Balantiocheilos melanopterus
Barbodes septemfasciatus
Betta coccina
Betta mahachai
Betta splendens
Boraras brigittae
Brachyrhaphis roseni
Brevibora dorsiocellata
Brochis splendens
Carassius auratus
Chindongo demasoni
Chromobotia macracanthus
Cichlasoma amazonarum
Corydoras aeneus
Corydoras habrosus
Corydoras paleatus
Cryptoheros chetumalensis
Cryptoheros cutteri
Crenicichla compressiceps
Cynotilapia zebroides
Danio rerio
Elassoma evergladei
Fundulus diaphanus
Gambusia holbrooki
Girardinus metallicus
Gymnocorymbus ternetzi
Gyrinocheilus aymonieri
Herichthys bartoni
Heros efasciatus
Herotilapia multispinosa
Hyphessobrycon anistitsi
Hyphessobrycon pyrrhonotus
Hyphessobrycon eques
Hypostomus plecostomus
Limia tridens
Lepomis megalotis
Lepomis cyanellus
Leporinus fasciatus
Macrotocinclus affinis
Melanotaenia lacistrus
Melanotaenia splendida
Metynnis argenteus
Mikrogeophagus altispinosa
Mikrogeophagus ramirezi
Misgurnus anguillicaudatus
Nannostomus beckfordi
Neolamprologus cygnus
Oryzias wowrae
Oscura heterospila
Panamius panamensis
Pangio shelfordii
Paracheirodon axelrodi
Paracheirodon innesi
Phenacogrammus interruptus
Poecilia latipinna
Poecilia reticulata
Poecilia salvatoris
Poecilia sphenops
Poecilia wingei
Pristella maxillaris
Pseudomugil gertrudae
Pterophyllum scalare
Pundamilia sp. black widow
Puntigrus tetrazona
Puntius titteya
Sundadanio margarition
Symphysodon aequifasciatus
Tanichthys albonubes
Thorichthys aureus
Trichopodus trichopterus
Vieja breidohri
Xenophallus umbratillis
Xenotoca doadrioi
Xiphophorus helleri
Xiphophorus maculatus
Xiphophorus pygmaeus
Xiphophorus variatus
Amatitlania kanna
Amatitlania myrnae
Amatitlania nanolutea
Amatitlania nigrofasciata (since siquia is about to become synonymized with nigrofasciata)
Amatitlania sajica
Amatitlania septemfasciata
Amphilophus labiatus
Amphilophus lyonsi
Amphilophus trimaculatus
Ancistrus cirrhosus
Ancistrus dolichopterus
Apyosemion australe
Ataeniobius toweri
Aulonocara stuartgranti
Balantiocheilos melanopterus
Barbodes septemfasciatus
Betta coccina
Betta mahachai
Betta splendens
Boraras brigittae
Brachyrhaphis roseni
Brevibora dorsiocellata
Brochis splendens
Carassius auratus
Chindongo demasoni
Chromobotia macracanthus
Cichlasoma amazonarum
Corydoras aeneus
Corydoras habrosus
Corydoras paleatus
Cryptoheros chetumalensis
Cryptoheros cutteri
Crenicichla compressiceps
Cynotilapia zebroides
Danio rerio
Elassoma evergladei
Fundulus diaphanus
Gambusia holbrooki
Girardinus metallicus
Gymnocorymbus ternetzi
Gyrinocheilus aymonieri
Herichthys bartoni
Heros efasciatus
Herotilapia multispinosa
Hyphessobrycon anistitsi
Hyphessobrycon pyrrhonotus
Hyphessobrycon eques
Hypostomus plecostomus
Limia tridens
Lepomis megalotis
Lepomis cyanellus
Leporinus fasciatus
Macrotocinclus affinis
Melanotaenia lacistrus
Melanotaenia splendida
Metynnis argenteus
Mikrogeophagus altispinosa
Mikrogeophagus ramirezi
Misgurnus anguillicaudatus
Nannostomus beckfordi
Neolamprologus cygnus
Oryzias wowrae
Oscura heterospila
Panamius panamensis
Pangio shelfordii
Paracheirodon axelrodi
Paracheirodon innesi
Phenacogrammus interruptus
Poecilia latipinna
Poecilia reticulata
Poecilia salvatoris
Poecilia sphenops
Poecilia wingei
Pristella maxillaris
Pseudomugil gertrudae
Pterophyllum scalare
Pundamilia sp. black widow
Puntigrus tetrazona
Puntius titteya
Sundadanio margarition
Symphysodon aequifasciatus
Tanichthys albonubes
Thorichthys aureus
Trichopodus trichopterus
Vieja breidohri
Xenophallus umbratillis
Xenotoca doadrioi
Xiphophorus helleri
Xiphophorus maculatus
Xiphophorus pygmaeus
Xiphophorus variatus