Not furry, but we like them anyway.
Wrestling Halfbeak
Dermogenys pusilla
Also called Malayan halfbeak, Silver halfbeak, Golden halfbeak
From Fresh and brackish waters of South-east Asia, described from Bogor, Java; reported from Thailand, Malaysia, Singapore, Sumatra and Borneo, with wider ranges given in some sources.123
A friendly guide, not veterinary advice. For anything about your pet's health, ask your vet.
At a glance the quick version
Looks how to spot one
Slender halfbeak
A thin, pencil-shaped surface fish with a long, fixed lower jaw. Males are smaller than females and have a modified anal fin used in mating.31
Personality what they are like
Timid at first but lively once settled. Males spar by locking jaws, though in aquaria the weaker fish usually backs off quickly without harm.13
Daily activity how busy a day looks
Active at the surface; an excellent jumper that needs a tight lid.3
Grooming and care the hands-on bits
Changes in pH and hardness should be made slowly. Floating plants give cover and help it feel secure.13
Home where they are happiest
Aquarium from about 60 x 38 x 30 cm (around 68 litres) for a small group, with a tight lid and floating plants. Water 24-28 °C, pH 6.5-8.0, 10-20 dGH. Copes with soft water through to slightly brackish.321
Food basics what goes in the bowl
Surface feeder: small insects such as fruit flies, mosquito larvae, brine shrimp and bloodworm; often learns to take dry food over time.312
Company who they like around
Calmer in groups. Keep either one male or several, with peaceful, similar-sized tankmates such as livebearers, rainbowfish or gobies.3
The story where it all began
Heinrich Kuhl and Johan Coenraad van Hasselt described the species in 1823 from Bogor on Java. Its common name comes from the males' habit of wrestling with locked jaws.1
Fun facts for the dinner table
Recognised by the official bits
- IUCN Red List
- Data Deficient (assessed 2020)2
- Taxonomy
- Family Zenarchopteridae; described by Kuhl and van Hasselt in 18231
The care rhythm Furry Diary remembers it for you
A typical home-care rhythm for a Wrestling Halfbeak. It is our own starting plan, not a vet's advice, and you can change every line in the app.
- FeedingSmall amounts once or twice a dayevery day
- Temperature checkevery day
- Water changeAbout 25% of the waterevery week
- Water testevery week
- Glass cleanevery week
- Filter rinseRinse in old tank water, never tap waterevery month
Owner questions the things everyone asks
How often should I feed my Wrestling Halfbeak?
Feed your Wrestling Halfbeak small amounts once or twice daily. Furry Diary's starting plan suggests feeding every day. They are surface feeders, so offer food that floats.312 Furry Diary plan
What does a Wrestling Halfbeak eat, and what should it never eat?
They eat small insects like fruit flies, mosquito larvae, brine shrimp and bloodworm, and often learn to take dry food. Avoid sinking or very large foods. For specific restrictions, ask your vet.312
How much space does a Wrestling Halfbeak need?
A tank of about 68 litres (60 x 38 x 30 cm) is suitable for a small group. They are active at the surface and need a tight lid to prevent jumping.321
What temperature, light or water does a Wrestling Halfbeak need?
Keep water at 24-28°C, pH 6.5-8.0, and hardness 10-20 dGH. They cope with soft to slightly brackish water. Provide floating plants for cover and a sense of security.321
How often should I clean a Wrestling Halfbeak's home?
Change about 25% of the water weekly, clean the glass weekly, and rinse the filter monthly in old tank water. Make changes to pH and hardness slowly. Furry Diary plan
Can a Wrestling Halfbeak live with others?
Yes, they are calmer in groups. Keep either one male or several, with peaceful tankmates like livebearers, rainbowfish or gobies. Males may spar but usually back off quickly.3
How long does a Wrestling Halfbeak live?
Lifespan varies depending on care. For typical longevity, ask a vet or a good breeder.
Can I handle a Wrestling Halfbeak?
Handling is not recommended as they are delicate. Use a net only when necessary. For health checks, consult an exotic-pet vet.
Written from the sources on this page, a few checked guides (VCA, ASPCA, RSPCA) and Furry Diary's own starting care plan. A friendly guide, not a vet's advice.
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Where this comes from
Every breed page shows where each fact comes from. If we got something wrong, sorry, we are pet people, not a science magazine. Tell us at support@furrydiary.app and we will fix it.
- Wikipedia: Dermogenys pusilla en.wikipedia.orgused for names, range, behaviour, history
- FishBase: Dermogenys pusilla fishbase.seused for environment, diet, IUCN
- Seriously Fish: Dermogenys pusilla seriouslyfish.comused for tank size, water, diet, behaviour
- VCA Animal Hospitals: Feeding times and frequency for your dog vcahospitals.comused for owner questions
- ASPCA: Dog grooming tips aspca.orgused for owner questions
- ASPCA: Cat grooming tips aspca.orgused for owner questions
- ASPCA: People foods to avoid feeding your pets aspca.orgused for owner questions
- RSPCA: What to feed your rabbit rspca.org.ukused for owner questions
Checked 2026-09-30. Text is written in our own words from these sources.