It’s found only in the Brazilian Amazon.
Forest streams and tributaries. The fish are most often found in areas with an abundance of surface vegetation.
Maximum Standard Length
Aquarium SizeTop ↑
24″ x 15″ x 12″ (60cm x 37.5cm x 30cm) – 27 litres.
Cover a good portion of the water surface with floating plants, which will help to make this flighty species less skittish. It also prefers a bit of current against which to swim. Other decor isn’t particularly critical, but it looks good in both heavily planted setups and Amazon biotope tanks, with driftwood branches, a sand substrate and some leaf litter. Make sure the tank cover is very tightly fitting, as it’s capable of clearing several metres in a single jump.
Temperature: 75-82°F (24-28°C)
Sometimes a little reluctant to take dried foods initially, but it will usually learn to accept them over time. A large proportion of the diet should consist of frozen and live foods, such as bloodworm and daphnia. Gut-loaded Drosophila fruit flies make an excellent food if they’re available.
Behaviour and CompatibilityTop ↑
Very peaceful but it can be nervous and shy, and will not compete well with boisterous species for food. Good tankmates include other small fish that inhabit different parts of the tank, such as tetras, dwarf cichlids and catfish such as Corydoras and Loricariids. Always buy at least half a dozen, as it won’t settle without the security of conspecifics.
Females are noticeably rounder-bodied than males when full of eggs.
This species spends almost all of its time at the water surface, although it will sometimes retreat into midwater if threatened or feeding. Like other freshwater hatchetfish, it’s renowned for its ability to fly for distances of several metres. This behaviour is used both to catch flying insects and to escape potential predators. As well as giving rise to the common name, the strange shape of the fish is thought to be involved in the ‘take-off’ and ‘landing’ phases of flight, the trenchant belly stabilising the fish at it exits and re-enters the water. It also has specialised fins. The pectorals are enlarged, and have massive muscles attached to them. The pelvic fins are reduced. The pectoral fins are actually beaten in a similar way to the wings of birds or insects during flight and an audible buzzing sound can often be heard as the fish moves through the air. The hatchetfish are the only known family of fish to employ powered flight, as opposed to the gliding behaviour seen in marine flying fish.
The silver hatchet can be quite delicate when initially imported, but once acclimatised proves to be a very good aquarium resident. It’s often confused with the common hatchet, G. sternicla, which confusingly is the species usually labelled as the silver hatchetfish in shops.