What tank mates can live with a betta in a 5-gallon (19 l) tank?

None, honestly: in 19–25 litres no species in our database passes every compatibility check alongside a betta. Keep him solo in a planted tank — that is the natural setup for this fish, not a downgrade.

Can a betta live with a gourami?

We advise against it: bettas and gouramis are close anabantoid relatives, and males frequently read each other as rivals — sparring and fin damage are a real risk even in larger tanks. Our engine carries a curated warning for exactly this pairing.

What are the best betta tank mates in a 112-litre tank?

Engine-green picks at this size: sterbai corydoras and clown plecos on the bottom, calm dwarf cichlids like the keyhole-tempered Laetacara or African butterfly cichlid, bamboo and vampire filter shrimp (too big to be prey), and a fast short-finned school such as glowlight tetras.

Why does every list of betta tank mates disagree?

Because individual temperament varies enormously and most lists don't state their tank size. A pairing that is red in 19 litres can be green in 112. This page states its conditions — moderately planted, four specific sizes — and recomputes from the engine on every update, so the advice can't silently drift from the calculator.

Betta tank mates, by tank size

No fish generates more contradictory advice than the betta — because no rule survives an individual's temperament. Even a pairing that has worked for months can end the day your betta decides otherwise. Every combination is a risk tier, not a guarantee, and a divider or a backup plan is part of responsible stocking.

That said, the risk tiers themselves are computable. Everything below comes live from our compatibility engine — the same temperament matrix, fin-nipping penalties, water-band intersections and curated rules as the calculator, evaluated in a moderately planted tank at four real tank sizes. When the engine finds nothing safe, the page says so.

19–25 litres · the 5-gallon tank

The honest answer: none. In this volume no species in our database passes every check alongside a betta — the footprint alone fails most of them. A well-planted 19–25 litre tank with one betta is not a compromise; it's the setup this fish is actually built for.

6 more species score amber here — workable for experienced keepers; check your exact combination in the calculator.

~54 litres · 60 cm starter

Still none — every candidate scores amber or worse once schooling minimums, swim space and the betta's temperament are all priced in. Some keepers do run 54-litre betta communities successfully, but that is experienced-keeper territory with a backup tank ready, not a starter recipe.

35 more species score amber here — workable for experienced keepers; check your exact combination in the calculator.

~112 litres · 80 cm community

This is where real options appear: armored bottom-dwellers that ignore the betta entirely, calm dwarf cichlids that hold their own space, big filter-feeding shrimp too large to be prey, and one fast, short-finned school.

Engine-green at this size

107 more species score amber here — workable for experienced keepers; check your exact combination in the calculator.

~240 litres · 120 cm showcase

Room changes everything: active mid-water schools get enough water to stay out of the betta's zone, and the green list grows accordingly. At this size the betta is the calm centerpiece of a busy community rather than its landlord.

Engine-green at this size

162 more species score amber here — workable for experienced keepers; check your exact combination in the calculator.

Common questions

What tank mates can live with a betta in a 5-gallon (19 l) tank?: None, honestly: in 19–25 litres no species in our database passes every compatibility check alongside a betta. Keep him solo in a planted tank — that is the natural setup for this fish, not a downgrade.
Can a betta live with a gourami?: We advise against it: bettas and gouramis are close anabantoid relatives, and males frequently read each other as rivals — sparring and fin damage are a real risk even in larger tanks. Our engine carries a curated warning for exactly this pairing.
What are the best betta tank mates in a 112-litre tank?: Engine-green picks at this size: sterbai corydoras and clown plecos on the bottom, calm dwarf cichlids like the keyhole-tempered Laetacara or African butterfly cichlid, bamboo and vampire filter shrimp (too big to be prey), and a fast short-finned school such as glowlight tetras.
Why does every list of betta tank mates disagree?: Because individual temperament varies enormously and most lists don't state their tank size. A pairing that is red in 19 litres can be green in 112. This page states its conditions — moderately planted, four specific sizes — and recomputes from the engine on every update, so the advice can't silently drift from the calculator.

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