African Knife Fish (Xenomystus nigri)
African Knife Fish (Xenomystus nigri)
African knife fish lack a dorsal fin entirely, relying only on a long undulating anal fin running most of the body’s length for propulsion — letting it hover, reverse, and maneuver with a precision dorsal-finned fish can’t match. It’s also an accessory air-breather, gulping air at the surface to supplement gills in the low-oxygen swamps and backwaters it calls home.
Care level: Moderate · Temperament: Peaceful, territorial with own kind · Max size: ~8" · Min tank: 40 gal · Diet: Carnivore, live/frozen foods
At a glance
- Scientific name
- Xenomystus nigri
- Common name
- African Knife Fish
- Water type
- Freshwater
- Care level
- Moderate
- Temperament
- Peaceful, territorial with own kind
- Max size
- ~8"
- Minimum tank
- 40 gal
- Diet
- Carnivore, live/frozen foods
When it ships
Most non-quarantined stock goes out the week you order. If we do not already have the animal in-house we source it first — allow up to two weeks for it to reach us. Live animals leave Monday and Tuesday, and Early AM Overnight is the only service that carries a live arrival guarantee.
The live guarantee
Shipped Early AM Overnight: a 1-hour DOA window from confirmed delivery, and nothing beyond it. Next Day Air and 2-Day carry no live arrival guarantee, and neither does USPS Priority. Local pickup or local delivery: 24 hours, if you bring a water sample from your aquarium and we test it before the animal goes home. Maintenance clients: 60 days when we service the aquarium at least twice a month, 28 days on a monthly plan.
Expert guidance
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