Search Species
Search for fish species by common or scientific name, or use filters to browse by water type, size, temperament, and difficulty.
Found 665 species
Wallace's dwarf pike cichlid
Wallaciia wallacii
A small "dwarf" pike cichlid (genus Wallaciia) from South America. Maximum recorded size is about 8.5 cm standard length; provide ample cover/structure and expect territorial behavior, especially around spawning.
Water hyacinth pencil catfish
Ituglanis eichhorniarum
Ituglanis eichorniarum is a tiny, secretive trichomycterid (pencil catfish) from the Paraguay-Parana system, the kind of fish that spends its time nosing through plants and leaf litter instead of cruising the open water. The species name comes from Eichhornia (water hyacinth), which is a fun clue to the sort of weedy habitat it was found in.
Wave Striped Oto
Otocinclus caxarari
Otocinclus caxarari is a very small Loricariid catfish from South America, recorded from the upper Madeira River basin (including the Guaporé area). In aquaria it is typically kept like other Otocinclus species: in mature, well-oxygenated tanks with abundant biofilm/algae and supplemental foods.
Wavyband sole
Zebrias japonicus
This subtropical western Pacific sole lives on sandy-mud bottoms. In aquaria it should be provided with appropriate soft substrate and be fed meaty, benthic-appropriate foods; use caution with tankmates due to its predatory nature.
Weed cardinalfish
Foa brachygramma
This is a tiny Hawaiian cardinalfish that hangs around sheltered shallows - think seagrass, algae, and rubble - and it even wanders into brackish and sometimes fresh water. Its vibe is classic cardinalfish: mellow, a little shy, and way more interesting once the lights go down. Also cool trivia: the males mouthbrood the eggs.
Weedy cardinalfish
Foa fo
Foa fo is a tiny little Indo-Pacific cardinalfish that hangs around sheltered reefy areas and weedy/mucky spots, usually staying pretty low-key and unobtrusive. Like other cardinalfish, the really cool bit is the breeding behavior - the male mouthbroods the eggs, so you will sometimes see a chunky-looking jaw when he is holding a clutch.
Western roeboides (scale-eating characin)
Roeboides occidentalis
Roeboides occidentalis is a wild characin from the Pacific-slope rivers of Panama down through Colombia into northern Ecuador, topping out around 13 cm (about 5 inches). The really interesting (and kinda spicy) thing about Roeboides as a group is the scale-eating tendency, so its tankmate choices need to be made with that in mind.
Whiptail catfish
Rineloricaria henselii
Rineloricaria henselii is a small loricariid (whiptail) catfish from southern Brazil (reported from the Cubatão River, Santa Catarina) reaching about 7.5 cm standard length.
Whiptail catfish
Rineloricaria sneiderni
This is a slim, leaf-perching whiptail from Colombia that blends into the sand and wood like a twig. It is mellow, spends a lot of time mouth-walking and sifting for tiny foods, and really shines in a clean, well-oxygenated, river-style setup.
Whiptail catfish (Twig catfish)
Farlowella acus
Farlowella acus is that classic twig-looking whiptail that can sit on wood and basically disappear - it really does look like a little stick with fins. It is super chill and spends most of its time grazing and picking at surfaces, so it does best in a mature tank with stable water and plenty of stuff to cling to.
Whitebanded sharpnose wrasse
Wetmorella albofasciata
This is one of those tiny, cryptic wrasses that spends a lot of time weaving through rockwork and poking into little cracks like it is on a constant scavenger hunt. The big eyes and sharp snout give it a weird-cute "mini predator" look, and it really shines in a peaceful reef where it feels safe enough to come out and cruise.
White-cheeked goby
Rhinogobius duospilus
This is one of those little stream gobies that acts like it's glued to the rocks-its pelvic fins form a suction-cup so it can hang out in flow. Males can color up really nicely and they'll claim a favorite cave/stone like a tiny bouncer, but in a well-structured tank they're super fun to watch cruise the bottom and perch.