Search Species
Search for fish species by common or scientific name, or use filters to browse by water type, size, temperament, and difficulty.
Found 275 species
Kanazawa sand lance
Ammodytoides kanazawai
Think of a tiny silver dart that lives to dive into sand - that is this little sand-burrowing planktivore from Japan’s Ogasawara Islands. It tops out around 6.3 cm and was described in 2013 from a specimen trawled at roughly 95-99 m off Chichijima, so you pretty much never see it in home aquariums. Neat fish to read about, but best left in the ocean unless you run a serious marine setup with open water and fine sand for it to rocket into. ([fishbase.se](https://fishbase.se/summary/Ammodytoides-kanazawai.html))
Kazunagi
Zoarchias veneficus
A tiny eel-like prickleback from Japans cool rocky shores, it threads through seaweed and crevices like a living shoelace. Tops out around 7 cm and spends its time peeking from rock cracks and snapping up tiny crustaceans, so a tank full of snug caves is its happy place.
Kelp gunnel
Ulvicola sanctaerosae
This is a skinny little kelp-forest perch that literally hangs out up in the kelp canopy and chills on the fronds. One of the coolest bits is how it uses its tail to wrap onto kelp like a grip, then picks off tiny crustaceans drifting by. Not really an aquarium trade fish, but its a super neat West Coast oddball if you ever see one while diving.
Kerala sole
Zebrias keralensis
This is a small, sand-hugging marine sole from the Kerala coast area, with that classic zebra-style banding that helps it vanish the second it settles onto the bottom. Its whole deal is staying low, burying in fine sand, and picking off tiny bottom critters - super cool fish, but not really something you see in the aquarium trade.
Kermadec dwarfgoby
Eviota kermadecensis
This is a true micro-goby from the Kermadec Islands (Raoul Island area) - the kind of tiny reef fish that basically lives in the nooks and crannies and makes you stare at your rockwork more. Its whole vibe is cryptic and subtle, but that is exactly why dwarfgobies are so addicting once you start noticing them.
Kimura's sole
Aseraggodes kimurai
Aseraggodes kimurai is a tiny little marine sole (flatfish) from the western Pacific that spends its life glued to the bottom, blending into sand and rubble like a living leaf. Its whole vibe is stealth and camouflage, and it is the kind of fish you forget is even there until it scoots and re-buries itself. Super cool animal, but honestly not really an aquarium fish because it is a specialized bottom-dweller that wants live micro-food and a mature sandbed.
Kuiter's deepsea clingfish
Kopua kuiteri
Kopua kuiteri is a tiny deepwater clingfish from southern Australia that lives way down on the seafloor, not in the usual home-aquarium world. It is the kind of fish that sticks to hard surfaces with a suction disc and is basically a cool biology oddball rather than something you will realistically keep at home.
Kulbicki's pipefish
Festucalex kulbickii
This is a tiny reef pipefish from the western-central Pacific that hangs around coastal reefs and blends in with bands and ridges like a little living piece of reef debris. Like other syngnathids, the male broods the eggs in a pouch, which is honestly one of the coolest fish-family flexes in the hobby. It is not a commonly kept aquarium fish, and there are basically no solid reports of long-term captive success for this exact species, so I would treat it as a specialist-only pipefish.
Lanceolate shrimpgoby
Tomiyamichthys lanceolatus
This is a little sand-bottom shrimp goby from sheltered lagoons and bays in the western Pacific. It hangs close to its burrow on fine sand or mud and does the classic goby thing of hovering and darting back to cover when spooked. The lance-shaped tail and the bold side blotches make it a really neat, understated fish if you are into sandbed micro-predators.
Large-eye bigscale
Poromitra megalops
Tiny deep-sea ridgehead from the Atlantic with huge eyes, living in cold, dark water hundreds of meters down. It tops out around two-and-a-half inches and hangs in the mesopelagic-bathypelagic zone, which is awesome to read about but not something you can realistically keep at home.
Leaf-nose legskate
Springeria folirostris
This is a deepwater skate from the Gulf of Mexico with a really funky leaf-like snout extension and those "leg-like" pelvic fins skates are famous for. It lives way down on soft mud/sand bottoms, so its whole vibe is slow, bottom-oriented, and built for cruising the seabed rather than darting around the water column.
Lombok viviparous brotula
Paradiancistrus lombokensis
This is a tiny, super-cryptic marine brotula from around Lombok, Indonesia - the kind of fish that lives tucked deep in reef cracks where you basically never see it. The really neat part is its group (viviparous brotulas) gives live birth, so its biology is way cooler than its shy little "hide in the rocks" lifestyle suggests.