
Wrestling Halfbeak
Dermogenys pusilla
Family: Zenarchopteridae • Origin: Various
Wrestling Halfbeak (Dermogenys pusilla) is a semi-aggressive other reaching 2.5 inches. Keep in groups of 3+. Minimum tank size: 10 gallons.
Is Wrestling Halfbeak Right for Your Tank?
Wrestling Halfbeak is an excellent choice for beginners — rated "intermediate" difficulty (2/5). They're hardy, forgiving of minor water parameter fluctuations, and generally easy to feed. At just 10 gallons minimum, they work well in nano tanks and smaller setups.
Wrestling Halfbeak is semi-aggressive — they can live with others but may bully smaller or slower fish. Choose tank mates carefully. This is a schooling species — keep at least 3 together, or they may become stressed and display abnormal behavior. They are territorial — provide adequate hiding spots and maintain enough space to reduce aggression. Expected lifespan: 4 years with proper care.
Common Mistakes with Wrestling Halfbeak
Keeping fewer than 3 together
Wrestling Halfbeak is a schooling species — they need a group of at least 3 to feel secure. Lone or paired individuals become stressed, hide constantly, and may develop health issues or aggression.
Relying on a heater without a thermometer
Wrestling Halfbeak needs 75–82°F. Heaters malfunction or drift over time — always use a separate thermometer to verify. Temperature swings of even 3–4°F can trigger stress and disease, particularly ich.
Putting them in a tank under 10 gallons
While 10 gallons is the minimum, nano tanks require more frequent water changes and leave less room for error. A slightly larger tank (15 gal) is much more forgiving.
Housing with peaceful nano fish
Wrestling Halfbeak is semi-aggressive and territorial — small, peaceful species like neon tetras, endlers, or celestial pearl danios will be stressed, bullied, or eaten. Choose tank mates that can hold their own.
Care Tips
- • Max size: 2.5 inches
- • Temperature: 75-82°F
- • pH: 7-8
- • Schooling — keep 3+ together
- • semi-aggressive temperament — choose tankmates carefully
Feeding: Standard carnivore diet. Accepts foods appropriate for Zenarchopteridae species.
Compatibility Notes: Typical semi-aggressive Zenarchopteridae species.
Tank Setup & Water Parameters
Tank Requirements
- Minimum Tank Size
- 10 gallons
- Recommended Tank Size
- 15 gallons
- Swimming Level
- top
- Minimum School Size
- 3+ fish
Water Parameters
- Temperature
- 75–82°F
- pH Range
- 7–8
- Hardness (dGH)
- 5–15
- Water Type
- freshwater
Behavior & Temperament
- Temperament
- semi-aggressive
- Aggression Level
- 3/5
- Schooling
- Yes
- Territorial
- Yes
- Fin Nipper
- No
- Predatory
- No
- Diet Type
- carnivore
- Growth Rate
- moderate
Typical semi-aggressive Zenarchopteridae species.
Breeding
- Breeding Type
- egg layer
- Breeding Difficulty
- moderate
- Lifespan
- 4 years
Ideal For
Compatible Tank Mates
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Guppy
Poecilia reticulata
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