Search Species
Search for fish species by common or scientific name, or use filters to browse by water type, size, temperament, and difficulty.
Found 654 species
Ram cichlid (German blue ram / butterfly cichlid)
Mikrogeophagus ramirezi
Rams are tiny little cichlids with big-time attitude (in the cutest way) and insane sparkle-those blues, yellows, and that black face bar really pop when they're happy. They're also one of the warmer-water dwarf cichlids, and they'll show off pair behavior and even spawn on flat stones if you keep the tank clean and calm.
Randall’s shrimp goby
Amblyeleotris randalli
Randall's shrimp goby is that little candy-cane striped goby you'll see parked at the entrance of a burrow, doing sentry duty like it's getting paid for it. The really fun part is the partnership with a pistol shrimp-goby keeps watch, shrimp does the digging, and they basically run a tiny construction site in your sand bed. Give it a cozy sand area and a few rubble bits and it'll settle in and start acting like it owns the place (in the cutest way).
Rao's hover goby
Parioglossus raoi
Tiny, zippy little dartfish that hangs in loose groups and hovers midwater like it is on invisible strings. The slim gold stripe and blue-rimmed eyes pop under reef lights, and they spend the day picking tiny zooplankton from the water column. Give them frequent small feedings and they settle in great with peaceful tankmates.
rattail
Kuronezumia macronema
A deep-sea rattail from the Philippines and the South China Sea, this fish cruises 600-800 m down where the water is cold and dark. It has that classic whiptail body and even a small light organ, picking off tiny crustaceans or scavenging what it finds. Super neat to learn about, but it is a look-only species for public aquariums, not something to keep at home.
Rattail (grenadier)
Ventrifossa rhipidodorsalis
Deep-water marine rattail (family Macrouridae) from the Western Pacific (reported from southern Japan, northeastern Taiwan, the South China Sea, and the Philippines) occurring around ~500–535 m depth. Notable ID features include a relatively large ventral luminous organ (photophore) between the pelvic-fin bases and a mostly dark first dorsal fin with pale/white areas basally and distally. This is a deep-sea species and is not an appropriate/realistic home-aquarium fish.
Redback dragonet
Synchiropus tudorjonesi
This is a tiny deepwater scooter dragonet from Indonesia/Papua New Guinea that spends its whole day glued to the bottom, pecking at micro-crustaceans in the sand and rubble. The cool part is the male's little "flag" dorsal fin display and that rich red banding - but it is absolutely the kind of fish that does best in a mature, pod-rich reef where it can hunt constantly. If you like watching behavior more than a fish "doing laps," this one is a total vibe.
Redlips Darter
Etheostoma maydeni
This is a tiny Cumberland River drainage darter with a really neat telltale feature: the red pigment right on the lips. Its whole vibe is hanging out on the bottom in calmer pools along big creeks and rivers, tucked around boulders and woody cover.
Red Neon Blue-eye
Pseudomugil luminatus
This little blue-eye is basically a tiny fireworks show-males flash electric blue eyes and red/orange fins and spend half the day showing off to each other. Keep them in a nice-sized group and you'll see constant "dancing" and fin-flaring in the open water, especially over dark substrate and plants.
Red-tailed tinfoil barb
Barbonymus altus
Picture a shiny silver barb with vivid red fins and a plain red tail - no black edging - that cruises nonstop like a little river torpedo. It looks a lot like the big tinfoil barb but stays smaller, topping out around 10 inches, and really comes alive when you keep a group in a long tank with good flow.
Renny's ricefish
Oryzias hadiatyae
Endemic to Lake Masapi (Malili Lakes system), Central Sulawesi, Indonesia; reported from shallow shoreline habitats and associated with shoreline root/vegetation structure. Diagnostic morphology includes a snout concavity (not unique within the genus).
Reticulate clingfish
Tomicodon lavettsmithi
This is a tiny little clingfish from the NW Caribbean that spends its life plastered to rubble and shells in super-shallow water. It has that classic clingfish suction disc, so it can hang on in surge and pick at small prey right on the bottom. Not really a "community tank" fish - its whole vibe is cryptic, rock-hugging micro-predator in a saltwater nano.
Reticulated hillstream loach
Sewellia lineolata
This is the little "stingray-shaped" loach that parks itself on rocks and glass like it's magnetized, then cruises around in the current like a tiny river skate. Give it cool, super-oxygenated, fast-moving water and lots of smooth stones with biofilm, and it'll spend all day grazing and doing hilarious little dominance shuffles with its own kind.