What fish can live with Brown / hockey-stick pencilfish?

Use the "Often compatible" lists as a shortlist, not a stocking plan. Always run the pair tool and check the footprint of your actual tank first. Verify behaviour for Brown / hockey-stick pencilfish against your own reading before you buy.

What tank mates should you avoid with Brown / hockey-stick pencilfish?

Avoid African Cichlid, Oscar, Pea Puffer based on size, temperament, or predation risk on file.

What size tank do Brown / hockey-stick pencilfish need for a community?

100L is the planning floor for adult swimming space and bioload headroom. Long-term, a 122L+ tank lets adults use the full footprint without crowding the next species. Footprint, meaning length and front-to-back depth, matters as much as raw volume for active or territorial species.

Brown / hockey-stick pencilfish tank mates

A 5 cm torpedo pencilfish that prefers blackwater soft conditions. Peaceful and shrimp-safe. Needs tannins and soft water for full lateral colouring.

Evidence: partially verified

Confidence: high

Lists below are built from this species record (safest, best with, risky, unsafe) — each link opens a pair-level check, not a guarantee.

← Full Brown / hockey-stick pencilfish profile·Compatibility checker·Tank builder·More barb

Best tank mates (on file)

Merged from conservative safest and best with fields — de-duplicated by species.

Corydoras Catfish Pair check
The Brown / hockey-stick pencilfish profile lists Corydoras Catfish as both safe and a recommended pairing. Corydoras Catfish schools in groups of 6 or more, so plan room for the whole group rather than one fish. Corydoras Catfish swims in the bottom zone while Brown / hockey-stick pencilfish stays in the top, so the two will not crowd the same water column.
Dwarf Gourami Pair check
The Brown / hockey-stick pencilfish profile lists Dwarf Gourami as both safe and a recommended pairing. Dwarf Gourami is a peaceful beginner-care species with a 60L minimum. Run the pair checker for your specific tank before stocking.
Ember Tetra Pair check
The Brown / hockey-stick pencilfish profile lists Ember Tetra as both safe and a recommended pairing. Ember Tetra schools in groups of 8 or more, so plan room for the whole group rather than one fish. Ember Tetra grows to about 2cm, which is borderline mouth-size for an adult 5cm Brown / hockey-stick pencilfish.
Harlequin Rasbora Pair check
The Brown / hockey-stick pencilfish profile lists Harlequin Rasbora as a recommended pairing. Harlequin Rasbora schools in groups of 6 or more, so plan room for the whole group rather than one fish.
Neon Tetra Pair check
The Brown / hockey-stick pencilfish profile lists Neon Tetra as both safe and a recommended pairing. Neon Tetra schools in groups of 6 or more, so plan room for the whole group rather than one fish.

Risky or situational

From risky tank mates and broad avoid with (excluding “unsafe” below). May work with species-only setups, more water, or mature systems — read the pair page.

German Blue Ram Open pair check
Marked risky or situational on the profile. Tank length and group size change the outcome more than a temperament label does.
Betta Open pair check
Betta is rated semi-aggressive, so expect chasing, fin damage, or display behaviour directed at Brown / hockey-stick pencilfish. Run the pair checker before stocking.
Angelfish Open pair check
Angelfish reaches 20cm and is flagged predatory or as likely to eat small fish. Adult-size Brown / hockey-stick pencilfish at 5cm is inside that gape range. Angelfish is rated semi-aggressive, so expect chasing, fin damage, or display behaviour directed at Brown / hockey-stick pencilfish. Run the pair checker before stocking.
Tiger Barb Open pair check
Tiger Barb is flagged as a fin-nipper and Brown / hockey-stick pencilfish carries the long-finned risk profile (veil tails, trailing fins). Expect torn fins within days unless the nipper is in a proper group and the long-finned fish has plenty of cover. Tiger Barb is rated semi-aggressive, so expect chasing, fin damage, or display behaviour directed at Brown / hockey-stick pencilfish. Run the pair checker before stocking.
Jack Dempsey Open pair check
Jack Dempsey reaches 25cm and is flagged predatory or as likely to eat small fish. Adult-size Brown / hockey-stick pencilfish at 5cm is inside that gape range. Jack Dempsey is rated aggressive, so expect chasing, fin damage, or display behaviour directed at Brown / hockey-stick pencilfish. Run the pair checker before stocking.

Fish to avoid with Brown / hockey-stick pencilfish

From the unsafe list — predation, aggression, or space rules on this profile.

African Cichlid See why (pair)
African Cichlid reaches 15cm and is flagged predatory. Brown / hockey-stick pencilfish at 5cm is prey-sized for it. African Cichlid is rated aggressive and Brown / hockey-stick pencilfish is rated peaceful. No community-style planning carries that gap.
Oscar See why (pair)
Oscar reaches 35cm and is flagged predatory. Brown / hockey-stick pencilfish at 5cm is prey-sized for it. Oscar needs at least 300L, far above the 100L minimum for Brown / hockey-stick pencilfish. The tank that houses one stresses the other. Oscar is rated aggressive and Brown / hockey-stick pencilfish is rated peaceful. No community-style planning carries that gap.
Pea Puffer See why (pair)
Pea Puffer conflicts with Brown / hockey-stick pencilfish on temperament, predation, or footprint. The juvenile size in a shop tank is not the figure that matters here.

Tank size and groups

Published minimum for Brown / hockey-stick pencilfish: 100L — group minimum 6 (schooling).
Compatibility changes when the tank is too short for turning, too little for a real school, or too warm for one species and not the other — that is why pair checks include tank context, not only temperament.
Nearest litre hub to this minimum: 100L hub.

Easier alternatives to consider

Conservative beginner-peaceful picks from the library — not replacements for reading, but a shorter on-ramp than this species for a first tank.

Plan before you buy

Pair checks for every mix, then multi-species stocking in the builder.

Open compatibility checker Tank builder

Filtration & heating

A 100L minimum tank for Brown / hockey-stick pencilfish needs a filter rated for at least 400L/hr turnover and a heater maintaining 24–28°C.

Filter buying guide →Heater buying guide →Beginner plants guide →