Search Species
Search for fish species by common or scientific name, or use filters to browse by water type, size, temperament, and difficulty.
Found 559 species
Tanaka's possum wrasse
Wetmorella tanakai
This is one of those tiny, sneaky reef wrasses that basically lives in the rockwork and pops out to hunt little micro-bugs all day. The red-orange body with thin white bars and those little "eye spots" on the fins make it a really cool "where did that fish come from?" kind of addition. It is super peaceful, but it does best in a mature reef where it can graze and not get pushed around.
Tanganyika lampeye
Lacustricola pumilus
This is a tiny Lake Tanganyika-area lampeye killifish that hangs in little groups along quiet shorelines and river-mouth shallows. When the light hits right, the males flash a really slick metallic eye and warm orange tones in the fins, and they are constantly out in the open cruising the edges for food.
Taquari banjo catfish
Ernstichthys taquari
This is a tiny little banjo catfish from Brazil that lives right on the bottom and blends in with rocks, sand, and leaf litter. Its known habitat is shaded, vegetated stretches of a small whitewater river with moderate flow and lots of big rocks - very much a hide-and-sit-still kind of fish. In the aquarium hobby its basically a "research fish" right now: super cool, but there is almost no species-specific care data published.
Tchefou cardinalfish
Jaydia tchefouensis
Jaydia tchefouensis is a little marine cardinalfish (Apogonidae) originally described from Chefoo/Tche-Fou (modern Yantai), China. Real talk: this name is kind of messy in the literature and may actually be a junior synonym of Jaydia lineata, so you will almost never see it sold under this exact ID in the aquarium trade. Like other cardinalfish, expect a shy, nocturnal vibe that hangs near structure and picks off small meaty foods.
Tequila splitfin
Zoogoneticus tequila
This is a little Mexican goodeid livebearer where the males get that awesome orange crescent in the tail and will spar and posture like tiny cichlids. They do best in a planted tank where they can duck into roots and stems, and once they're settled they'll breed steadily and you'll see lots of interesting social behavior.
Thracian shemaya
Alburnus istanbulensis
Endemic to Turkey, occurring in coastal streams of Thrace (Marmara to SW Black Sea drainages) and Lake Sapanca; a small, silvery pelagic cyprinid (bleak/shemaya type).
Threadfin rainbowfish
Iriatherina werneri
This is the little rainbowfish with the ridiculous, delicate streamers - especially on the males, who love to posture and "dance" at each other in a calm planted tank. Keep them in a real group and they get way braver, cruising the top/midwater under floaters and showing off those thread-like fins. They are peaceful, but they really hate fast flow and rough tankmates that shred fins or outcompete them at feeding time.
Threadfin seasnail
Rhodichthys regina
This is a deep-sea snailfish from the Arctic and far North Atlantic - not an aquarium fish at all, but a really neat oddball from way down in the cold and dark. It lives on or right above the bottom and cruises around picking off crustaceans, and in life it can be bright red which is wild for something from 1000+ meters down.
Three-lined aphyosemion (three-lined killifish)
Aphyosemion trilineatus
Aphyosemion trilineatus is a small West African killifish from Cameroon that does best in a calm, plant-heavy setup with gentle filtration and a tight lid (they can jump). Males top out around 5.1 cm and look way flashier than females, and like most Aphyosemion they are happiest when you keep things on the soft, slightly acidic side and do changes slowly.
Three-spined stickleback
Gasterosteus aculeatus
The three-spined stickleback is a small, armored fish with bony lateral plates and three prominent dorsal spines used for defense. Males become striking in breeding condition, often developing a red throat/belly and intensified coloration while they build and guard nests. It is highly active and behaviorally interesting, but can be nippy and territorial, especially during breeding.
Three-spot righteye flounder
Samariscus triocellatus
This is a tiny little Indo-Pacific flounder that lives right on sand and rubble around reefs, and it can be ridiculously hard to spot once it settles in. The coolest part is the three eye-like spots (ocelli) and the way it kind of creeps along the bottom hunting small benthic critters at dusk.
Tidepool snailfish
Liparis florae
This is a little coldwater snailfish that literally lives in tide pools on exposed Pacific coast rock, hiding under algae and stones when the surf is crashing. It has that classic soft, tadpole-ish snailfish look and a suction-disk belly, so it can cling in place instead of getting tossed around. Super cool fish biologically, but it is absolutely not a normal home-aquarium species unless youre set up for a chilled marine system.