35 compatibility guides
Tank mates, with the difficult parts left in.
Each guide separates promising, conditional and unsuitable directions and links back to the care profiles behind the conclusion.
Betta tank mates
Calm movement, gentle flow and no fin-nipping matter more than simply matching temperature.
Focal profile: Betta fishAngelfish tank mates
Adult mouth size and territorial breeding behaviour are the two constraints most often missed.
Focal profile: Freshwater angelfishPea Puffer tank mates
A species-focused setup is the most predictable plan because even tiny puffers are territorial hunters.
Focal profile: Pea pufferGoldfish tank mates
Temperature, adult size and feeding speed sharply limit conventional community choices.
Focal profile: Common goldfishTiger Barb tank mates
A large barb school reduces but never guarantees an end to fin-nipping.
Focal profile: Tiger barbAxolotl tank mates
Cool water, delicate gills and ingestion risk make species-only housing the welfare-led default.
Focal profile: AxolotlAfrican Dwarf Frog tank mates
Slow feeding and the need to reach the surface are decisive constraints.
Focal profile: African dwarf frogElectric Blue Acara tank mates
Robust companions can work outside breeding periods when the footprint provides separate territories.
Focal profile: Electric blue acaraDwarf Gourami tank mates
Surface territory, bright lights and fin-nipping should all be managed.
Focal profile: Dwarf gouramiOscar tank mates
Tank mates must be too large to swallow, robust enough to coexist and supported by exceptional filtration.
Focal profile: OscarRainbow Shark tank mates
Choose upper-water swimmers and leave the bottom territory to a single shark.
Focal profile: Rainbow sharkGourami tank mates
A calm upper layer and visual cover suit the gourami's surface-oriented behaviour.
Focal profile: Pearl gouramiGuppy tank mates
Hardness compatibility and protection of flowing fins define the shortlist.
Focal profile: GuppyRed Tail Shark tank mates
One territorial bottom fish per footprint is the safest planning rule.
Focal profile: Red tail sharkKuhli Loach tank mates
Peaceful upper-water companions preserve the loach's nocturnal access to food and shelter.
Focal profile: Kuhli loachDiscus tank mates
Sustained high temperature rules out many fish that look compatible on temperament alone.
Focal profile: DiscusBlue Acara tank mates
Adult size and breeding territories should be planned before the fish are introduced.
Focal profile: Electric blue acaraConvict Cichlid tank mates
A breeding pair can dominate an entire aquarium, so no generic community promise is responsible.
Focal profile: Convict cichlidFemale Betta tank mates
Female bettas are still territorial; sex does not turn the species into a guaranteed community fish.
Focal profile: Betta fishPictus Catfish tank mates
Anything mouth-sized may disappear at night, and long swimming space is essential.
Focal profile: Pictus catfishNeon Tetra tank mates
A large shoal with calm, similarly sized companions is more reliable than a crowded mixed collection.
Focal profile: Neon tetraBichir tank mates
The adult bichir's mouth size and nocturnal hunting behaviour are the primary filter.
Focal profile: Senegal bichirCichlid tank mates
Cichlid is not one temperament category; this guide is scoped to medium Central American species.
Focal profile: Firemouth cichlidCherry Shrimp tank mates
Shrimplet survival is a different standard from adult shrimp survival.
Focal profile: Cherry shrimpCrayfish tank mates
Claws, moulting vulnerability and night-time contact prevent any zero-risk pairing.
Focal profile: Dwarf Mexican crayfishHoney Gourami tank mates
Gentle shoalers and soft visual cover help the shy gourami feed confidently.
Focal profile: Honey gouramiBumblebee Goby tank mates
Bumblebee gobies vary by species and salinity need; confirm the scientific identity and water type before considering any companion.
Focal profile: bumblebee gobyGreen Terror tank mates
Only very large systems can provide meaningful escape distance from an adult territorial cichlid.
Focal profile: Green terror cichlidJack Dempsey tank mates
Match adult robustness, not shop size, and expect individual variation.
Focal profile: Jack Dempsey cichlidBala Shark tank mates
The enormous, skittish school determines the aquarium before any companion is considered.
Focal profile: Bala sharkCongo Tetra tank mates
A long aquarium, a proper shoal and protection of the Congo tetra's extended fins shape the shortlist.
Focal profile: Congo tetraFiremouth Cichlid tank mates
Visual barriers and an unused spawning territory make a major difference.
Focal profile: Firemouth cichlidGerman Blue Ram tank mates
Warmth and bottom-territory conflicts eliminate many otherwise peaceful candidates.
Focal profile: German blue ramCorydoras tank mates
Protect the bottom group's feeding access and avoid aggressive cave owners.
Focal profile: Bronze corydorasMolly tank mates
Hard, alkaline water is the deciding constraint more often than temperament.
Focal profile: Molly