Should I buy it?
Ropefish / reed fish
Erpetoichthys calabaricus
Also known as: ropefish, reed fish
An eel-like fish at 30 cm that eats anything small enough to swallow. Peaceful with fish its own size. Can escape through any gap and breathes air.
Ropefish / reed fish tank mates · 200L tank size hub
peaceful · advanced care
Sources & confidencehigh · partially verified · beginner: caution
Checked against several solid care sources that mostly agree. Numbers here are a careful starting point. Your tap water, tank size, and habits decide the rest. How we evaluate.
Best for: Large community tanks 200L or more with fish all over 8 cm, a fully sealed lid, and sand or fine gravel.
Avoid if: Any tank with small fish, tetras, or shrimp, or any lid with gaps.
Common mistakeLeaving no lid on a ropefish tank is how keepers invent a dried fish on the floor overnight. They push through surprisingly small openings without effort. Use a tight cover, hide spaghetti tubes, and plan 200L-class length — escape risk is ownership fact, not a rare accident story.
Top things that go wrong
- Mouth gap vs tiny tank mates. May eat tank mates small enough to fit the adult mouth — plan adult sizes, not shop sizes.
- Specialist husbandry. Keep at least 2, bought at the same time.
- Shrimp & snails. Not shrimp-safe — adults, fry, or both get eaten.
What most shops don't tell you
- 1.Myth: ropefish are hardy peaceful eels that stay put in open-top community tanks living on leftover flake. Reality: they escape through tiny gaps, need meaty night feeds, and will eat mouth-sized tank mates — cover and diet are non-negotiable ownership rules.
- 2.Predation risk scales with gape, night feeding, and crowding. 'they grew up together' is a schedule, not a law.
- 3.Classed peaceful for similar-sized community use. Still a bite-sized risk toward fry or very small comm fish in small volumes.
- 4.Loose glass covers with a 5 mm cut-out. A rope slips through and dries on the carpet.
- 5.Kept under 22 °C in winter. The fish stops feeding and goes into a slow decline.
- 6.Buy two or three from the same import. A loose lid is the leading killer: rope through a 5 mm gap, then dry on the carpet. Use a sealed cover and guard filter intakes against the snout.
- 7.Advanced species — research stable parameters before buying.
About this species
Ropefish are eel-shaped polypterids from West Africa that gulp atmospheric air at the surface and squeeze through any gap in a lid. Adults reach 30 to 40 cm and live in loose groups, so a 200 L covered tank is the realistic base.
- African freshwater butterflyfish150L min · same fish family
- Senegal bichir300L min · same fish family
- Golden Wonder Killifish80L min · same fish family
- American Flagfish60L min · same fish family
- Marbled Hatchetfish60L min · same fish family
- Clown Killifish20L min · same fish family
- Black ghost knifefish500L min · same fish family
- Discusalso advanced peaceful, similar tank size
- Hillstream Loachalso advanced peaceful, similar tank size
No reverse lookups listed yet.
Plan grid
Key limits are above. Here: pH band, swim level, bioload, and activity.
Swim zones
Care snapshot
Quick compare before you buy. Not a score of how “good” the fish is.
- Beginner ease14
- Peacefulness58
- Community fit23
- Small-tank fit80
- Hardiness36
- Energy24
Numbers are deterministic planning indices from Fishori fields — not a scientific score of your individual fish.
Example setups
Starting points only. Run the pair checker for every fish you add.
Rough 200L+ layout: one calm centrepiece, 8–12 small tetras/rasboras, 6–8 corydoras-type bottom fish — verify every name in the pair checker before buying.
Safer directions include: Bala / silver shark, Pictus catfish.
Compatibility
Tank mates for Ropefish / reed fish
Usually safer (engine GOOD): Bala / silver shark, Pictus catfish. Conditional (CAUTION — read the pair page before buying): Boesemani Rainbowfish, Giant danio. Avoid (RISKY): Chili Rasbora, Corydoras Catfish, Ember Tetra, Guppy, Neon Tetra. Every name links to a live pair check — the lists are a shortlist, not a stocking plan.
Usually safer
Open a pair page with this fish as the starting point.
Needs planning
Read the blocking rule on each pair page before experimenting.
Usually avoid
Do-not-stock combinations on conservative hobby rules.
Compare with
Run a real pair check: Ropefish / reed fish + Bala / silver shark
Behaviour and temperament
Ropefish are generally peaceful toward fish too large to eat, but predation risk scales with gape and night hunting. They stay calmer with cover tubes and honest tank length. Stress shows as frantic glass-searching when the lid is wrong or the tank is far too short.
What sets them off
- Sudden crowding
- Poor water quality
Fin nipping: Not a habitual fin-nipper; stressed or crowded individuals can still test fins.
Predation: May eat tank mates small enough to fit the adult mouth — plan adult sizes, not shop sizes.
Territory: Not strongly territorial, but still needs room so its working space does not overlap the next fish.
Planted tanks: good — easy plant ideas
In the glass: typical and warning signs
- Ropefish rest in tubes by day and patrol after lights soften.
- Tongue-flicking investigation of décor is normal ownership.
- Repeated escape attempts mean lid gaps failed before anything else.
- A thin nocturnal fish on flake alone usually means night feeding failed.
- Low malice toward robust similarly sized fish.
- Small fish and shrimp can disappear as mouth-size prey at night.
- Seal every lid gap the same day you add the fish.
- Remove nano livestock before blaming mystery disappearances.
Fish behaviour can vary between individuals and tank setups. Always observe new fish closely after introduction.
Water, food, and grouping
Hardness
soft
Diet
carnivore
Ropefish are nocturnal carnivores that need meaty foods — frozen bloodworm, prawn, and quality carnivore items — offered after lights soften. Flake-only community feeding leaves them thin while they hide all day under décor. Feed deliberately at night, keep a group of two or more when possible, and never treat them as scavenger leftovers eaters alone.
Shrimp & snails
Not shrimp-safe — adults, fry, or both get eaten.
Keep at least 2, bought at the same time.
- Hold 24 to 30 °C steadily on a real thermometer, not the dial on the heater.
- Aim for pH 6 to 7.2 and a hardness you can re-test in two weeks. A one-time strip in the shop car park is not a water test.
- Schooling species. Buy 2 or more from the same tank on the same day before adding any centrepiece fish.
- Tank volume meets or exceeds 200L published minimum for adults.
- You can stock at least 2 individuals (group welfare).
- Heater can hold 24–30°C without cooking cooler-water tank mates.
- No known fin-nippers paired with long-finned fish unless you accept documented risk.
- No tank mates small enough to fit the adult mouth gap for this species.
- Filter maturity / stable parameters before adding sensitive stock.
Explore and stocking hubs
Tank-mates hub, matching guides, category peers, and litre stocking lists around this species’ minimum tank.
Plan with tools
Check mates as pairs first, then add this fish in the tank builder for the full stocking.
Filtration & heating
A 200L minimum tank needs a filter rated for at least 800L/hr turnover and a heater to hold 24–30°C reliably.
Plant suggestions
Ropefish / reed fish does well in planted tanks. Plants compatible with 24–30°C and pH 6–7.2:
Research: partially verified · Confidence: high · 3 linked source(s). We do not invent citations.
How Fishori evaluates compatibility (same logic as pair and tank tools).
- Seriously Fish. Erpetoichthys calabaricus
Primary: aquarium size, water chemistry, behaviour, and compatibility (URL verified in upgrade script; recheck if site content changes).
- FishBase. Erpetoichthys calabaricus
Secondary: taxonomy, distribution, and maximum length in nature; cross-check with aquarium import lines and measured tank parameters.
- Wikipedia. Erpetoichthys calabaricus
Secondary: general species context; verify all husbandry numbers against a dedicated aquarium care sheet and your test kit, not a single table row.
Evidence notes
- The Seriously Fish profile for the binomial in this record was successfully reached as the primary aquarium reference.
- FishBase contributes natural-range size and habitat context. Translate those numbers through your heater, your water report, and your tank footprint before stocking.
- Wikipedia is only cited if the article URL returned OK. Use it for orientation, not as the only care sheet for an import.
- All compatibility text reflects typical hobby experience and the Fishori model. Individual fish, shop stress, and the order tank mates are added in can still defy a single-paragraph label.
Common questions about Ropefish / reed fish
- How big do Ropefish / reed fish get?
- Ropefish / reed fish adults run about 25–35 cm. In home tanks they usually land near 30 cm — plan space and filtration for that, not the juvenile in the shop bag.
- What size tank does Ropefish / reed fish need?
- 200L is the planning floor for adult swimming space and bioload. A 250L+ tank is the more comfortable long-term footprint. Length and depth matter as much as raw litres for active or territorial fish.
- Are Ropefish / reed fish aggressive?
- Ropefish are generally peaceful toward fish too large to eat, but predation risk scales with gape and night hunting. They stay calmer with cover tubes and honest tank length. Stress shows as frantic glass-searching when the lid is wrong or the tank is far too short.
- What is the most common mistake with Ropefish / reed fish?
- Leaving no lid on a ropefish tank is how keepers invent a dried fish on the floor overnight. They push through surprisingly small openings without effort. Use a tight cover, hide spaghetti tubes, and plan 200L-class length — escape risk is ownership fact, not a rare accident story.
- What fish can live with Ropefish / reed fish?
- The Ropefish / reed fish profile lists Bala / silver shark, Pictus catfish among its safer pairings (engine-checked GOOD). Boesemani Rainbowfish, Giant danio are conditional (CAUTION): workable only with the specific conditions on each pair page. Avoid Chili Rasbora, Corydoras Catfish, Ember Tetra, Guppy (RISKY). Run the pair checker for your exact water and tank size before stocking.