Longnose Gar

The longnose gar (Lepisosteus osseus) is a primitive, pike-like North American fish with a long, toothed snout and diamond-shaped ganoid scales, native from the St. Lawrence and Great Lakes through the Mississippi basin to the Gulf slope, and south into Mexico. It lives in sluggish pools, backwaters, oxbows and lakes, usually near vegetation, and occasionally enters brackish water. It is IUCN Least Concern and widespread, reaches 200 cm, and is an air-breathing fish whose eggs are poisonous - a legally regulated species in several US states even where it is native.

Wild longnose gar reach up to 200 cm and 22.8 kg, with Virginia Tech's adult range at 67-115 cm and first maturity around 67 cm; the profile's 100 cm is a fair mid-range adult, not the ceiling. They are long-lived - 36 years is the maximum reported age - so the enclosure is a multi-decade commitment. Young fish grow fast (about 30 cm in the first year when well fed), so a small tank fails quickly rather than slowly.

Longnose gars are sedentary ambush predators: they hang motionless near vegetation or float at the surface - where gulping air looks like basking - then explode forward in a sudden attack on passing fish. They are not documented as territorial aggressors; the real social problem is size, since anything not much larger than them is prey while larger active fish harass a sedentary gar in return. Expect a fish that uses the whole floor to turn, rests in open water rather than caves, and needs space to accelerate without hitting its snout.

Plan for an adult of up to 200 cm in a specialist aquarium of about 3,000 litres on the order of 300 x 100 cm of floor, with robust filtration and as wide a tank as possible to prevent injury to the long snout. Cover the tank, because gars are surface-dwellers that jump - but never seal it: gars breathe atmospheric air and must be able to break the surface, or they drown even in well-oxygenated water. Keep hardscape minimal (driftwood and rockwork only in exceptionally large setups), provide floating and submerged plant cover, and give it open floor rather than a decorated display. Confidence note: medium-confidence guidance drawn from published species care information; treat as conservative guidance, not a precise requirement.

Judge the tank by width first, not litres: NANFA's rule is keep gar in as wide an aquarium as possible to prevent injury to their large snouts, so a tall, narrow tank that hits a litre target is exactly the wrong shape. The implied floor is on the order of 300 x 100 cm, with the middle kept clear and plant cover at the edges rather than hardscape in the turning space. Volume alone is meaningless if the fish cannot turn without hitting its snout on the glass.

Carnivore with a feeding problem: wild fish take fishes, crayfish, crabs, insects and frogs, and gars are reputed to be voracious. In aquaria they may refuse anything but live fish, so the skill is weaning - NANFA's documented route is to use food the fish associates with the keeper and gradually switch to floating pellets, with frozen smelt and beefheart accepted by adults. Young gar grow fast and waste away if underfed, so feed adequately while growing them out - but avoid feeder fish where possible (disease risk) and never rely on them as the whole diet.

Compatibility is a narrow corridor with two walls: anything not much larger than the gar is eaten, while larger, more active tankmates harass the sedentary gar. In practice that leaves species-only housing for most keepers, or genuinely large, calm tankmates in an exceptionally large tank - and invertebrates such as crayfish and crabs are prey, not cleanup crew. Secure the setup as well: a long-snouted, surface-breathing fish that startles will test both the cover and the equipment.

Verdict: an expert-only specialist fish - a 1-2 m, air-breathing ambush predator that needs about 3,000 litres of wide, sparsely decorated floor, a cover that keeps jumps in but air available, and decades of commitment (36 years is the reported maximum age). The daily reality is a carnivore that may accept only live fish until weaned to pellets, with a poisonous roe to keep out of reach of children and pets. Skip it unless you can fund a very large specialist setup, sustain a meaty feeding regime, and check that keeping gar is legal where you live - in much of its native range it is regulated even for natives. Confidence note: medium-confidence guidance drawn from published species care information; treat as conservative guidance, not a precise requirement.