Wrestling halfbeak

Dermogenys pusilla

Also known as Dermogenys pusillus

FreshwaterBrackishFish

Care at a glance

Temperature
75–82°F
24–28°C
pH
6.5–7.5
Adult size
2.8 in
7 cm
Minimum tank
25 gal
95 L
Temperament
Mostly peaceful
Social behavior
Social
Swim level
Top
Difficulty
Medium
Breeding
Hard
Rarity
Rare
Family
Zenarchopteridae
Origin
Southeast Asia

Overview

The wrestling halfbeak is a slender surface fish that should be kept in a group, either one male with several females or, in a longer tank with lots of cover, a larger mix. It is peaceful toward other species, though males lock jaws and wrestle over space, and in a small tank these bouts can cause injury, so give them room and sight breaks with floating plants. It feeds at the top on small insects and larvae, so offer frozen and live foods along with a floating flake. It likes hard, neutral water and does well with a little salt, matching its part-brackish home. Give a group a covered tank of 95 liters or larger, since it stays at the surface and jumps.

In the wild

Dermogenys pusilla lives across Southeast Asia in fresh and brackish waters, from rice paddies and ditches to slow rivers and coastal creeks. It is used to warm, hard water, so keep a temperature between 24 and 28 C and a pH from about 6.5 to 7.5, with a little marine salt if you like. A tank with floating plants, open surface and gentle flow suits it, and a tight lid is essential for this surface-hugging jumper. Calm, clean water helps it settle.

Good to know

The wrestling halfbeak is a livebearer in the halfbeak family Zenarchopteridae, reaching about 7 cm, with the long lower jaw that gives the group its name. The male fertilizes the female internally using an andropodium, a modified anal fin, and she carries the young until they are born free-swimming. Broods are small and the delicate fry are easily lost, so it is one of the harder livebearers to breed reliably.

Did you know

The name comes from the way rival males grip each other by the beak and shove in trials of strength, contests that hobbyists in parts of Southeast Asia have long staged as a form of fish fighting.

Weekly picks

Tank mates

Wrestling halfbeak is a mostly peaceful, social species that keeps to the top. These picks share a community profile with it, are safe together in both directions, and overlap on water type, temperature and pH.

Check the full mix in the stocking calculator

Common questions

What size tank does a Wrestling halfbeak need?

A Wrestling halfbeak needs at least 25 gal (95 L). It spends most of its time in the top.

What temperature and pH does a Wrestling halfbeak need?

A Wrestling halfbeak is comfortable at 75–82°F (24–28°C) with a pH of 6.5–7.5.

How big does a Wrestling halfbeak get?

An adult Wrestling halfbeak reaches about 2.8 in (7 cm).

Related species