Compatibility brief
Can Black ghost knifefish live with Neon Tetra?
Risky. This mix is commonly discouraged for typical setups.
Compatibility score
Profile confidence: low
How we decideFishori checks adult size and predation risk, behaviour, water requirements and tank needs before giving a verdict.
500L
Combined minimum footprint reference for these two species: about 500L (larger active fish often want more length).
Black ghost knifefish (about 45cm as an adult) can realistically eat Neon Tetra (about 4cm) once grown. Plan around adult sizes, not shop sizes.
Temperament gap (semi-aggressive vs peaceful) adds stress on top of the hard incompatibility — space and cover do not make this pairing safe.
Assessment details
Temperament difference
Black ghost knifefish is semi-aggressive, while Neon Tetra is peaceful. Expect chasing or stress unless the tank is large and heavily structured — monitor closely.
Black ghost knifefish may eat Neon Tetra
Top issueBlack ghost knifefish (45cm) is predatory and Neon Tetra (4cm) is small enough to be eaten. This pairing is unsafe.
Narrow temperature overlap
Black ghost knifefish and Neon Tetra have only a narrow shared temperature range. Maintaining stable water temperature will be important.
“Black ghost knifefish (45cm) is predatory and Neon Tetra…”
Black ghost knifefish may eat Neon Tetra
Next steps
Concrete changes, not "research more" filler.
- •Provide plenty of hiding spots and visual breaks so Neon Tetra can escape if harassed.
- •Neon Tetra should be kept in a group of at least 6 for best health and behaviour.
- •Black ghost knifefish reaches ~45cm: tank length and turning room matter more than the litre number. A tall, short tank of the same volume is not equivalent.
Try instead
- →Build a species-only tank for the larger fish, or restock with fish too large to be eaten at adult sizes.
- LiveAquaria. Black ghost knifefish (Apteronotus albifrons care sheet)
Primary: large-aquarium retailer care profile: very large tank, dim lighting, hiding, carnivore diet, and size expectations. Cross-check the stated minimum with your own footprint and filtration; Fishori uses a stricter home-aquarium minimum than a catalog line.
- FishBase. Apteronotus albifrons
Secondary: natural history and max length; weakly electric foraging in the dark. Translate into tank length and nocturnal feeding, not a neon-tetra list.
- Seriously Fish. Paracheirodon innesi
Supports: aquarium size, water chemistry, temperament and compatibility (primary care reference).
- FishBase. Paracheirodon innesi
Supports: taxonomy and wild maximum size — translate to tank stocking, not a target number.
- Wikipedia. Paracheirodon innesi
Supports: general species background and common-name orientation only.
Try this next
Build the full stocking list with Black ghost knifefish + Neon Tetra
Plan further
Check each species’ mates list, size the glass, then verify the full stock in the builder. Methodology explains how verdicts are produced.
Individual fish vary in personality. Fishori uses conservative hobby rules. Observe any new introduction closely, feed thoughtfully, and keep a quarantine or backup plan. This is not veterinary advice.
Profile data confidence: medium. Driven by the lower-confidence profile (Black ghost knifefish): Typical care sources — real tanks still vary.