What fish can live with Opaline gourami?

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 Opaline gourami against your own reading before you buy.

What tank mates should you avoid with Opaline gourami?

Avoid Betta, Chili Rasbora, Pea Puffer based on size, temperament, or predation risk on file.

What size tank do Opaline gourami need for a community?

150L is the planning floor for adult swimming space and bioload headroom. Long-term, a 183L+ 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.

Opaline gourami tank mates

A large semi-aggressive gourami at 15 cm with blue-green marble patterning. Males fight other gouramis and harass slower community fish.

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 Opaline gourami profile·Compatibility checker·Tank builder·More gourami

Best tank mates (on file)

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

Boesemani Rainbowfish Pair check
The Opaline gourami profile lists Boesemani Rainbowfish as both safe and a recommended pairing. Boesemani Rainbowfish schools in groups of 6 or more, so plan room for the whole group rather than one fish.
Congo Tetra Pair check
The Opaline gourami profile lists Congo Tetra as a recommended pairing. Congo Tetra schools in groups of 8 or more, so plan room for the whole group rather than one fish.
Corydoras Catfish Pair check
The Opaline gourami 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 grows to about 6cm, which is borderline mouth-size for an adult 15cm Opaline gourami. Corydoras Catfish swims in the bottom zone while Opaline gourami stays in the top, so the two will not crowd the same water column.
Dwarf Gourami Pair check
The Opaline gourami profile lists Dwarf Gourami as 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.
Molly Pair check
The Opaline gourami profile lists Molly as both safe and a recommended pairing. Molly is a peaceful beginner-care species with a 80L minimum. Run the pair checker for your specific tank before stocking.
Swordtail Pair check
The Opaline gourami profile lists Swordtail as a safe tank mate. Swordtail is a semi-aggressive beginner-care species with a 80L minimum. Run the pair checker for your specific tank before stocking.

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.

Neon Tetra Open pair check
Marked risky or situational on the profile. Tank length and group size change the outcome more than a temperament label does.
German Blue Ram Open pair check
Both species defend territory. The pairing needs a long footprint and rockwork or planting that breaks the sightline between two defended spots. Run the pair checker before stocking.
Guppy Open pair check
Marked risky or situational on the profile. Tank length and group size change the outcome more than a temperament label does.
Ember Tetra Open pair check
Listed under broad avoid-with planning on the profile. The pair page covers what makes it situational.

Fish to avoid with Opaline gourami

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

Betta See why (pair)
Opaline gourami is flagged as predatory or as likely to eat small fish, and Betta at 7cm is well within an adult Opaline gourami's gape.
Chili Rasbora See why (pair)
Opaline gourami is flagged as predatory or as likely to eat small fish, and Chili Rasbora at 2cm is well within an adult Opaline gourami's gape.
Pea Puffer See why (pair)
Opaline gourami is flagged as predatory or as likely to eat small fish, and Pea Puffer at 3cm is well within an adult Opaline gourami's gape.

Tank size and groups

Published minimum for Opaline gourami: 150L — group minimum 1 .
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: 160L 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 150L minimum tank for Opaline gourami needs a filter rated for at least 600L/hr turnover and a heater maintaining 22–28°C.

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