Aquarium species profile

Threadfin Rainbowfish

Iriatherina werneri · New Guinea and northern Australia

Minimum tank10 gal

Adult size1.5"

Care levelModerate

TemperamentPeaceful

Temperature75–82°F

pH range6.0–8.0

Diet

Omnivore – micro foods, infusoria, live baby brine shrimp, micro pellets

Compatible tank mates

Micro fish only — small rasboras, micro tetras, shrimp

Tank mates to avoid

Any fish large enough to nip fins (the long fin extensions are delicate)

Care notes

Tiny and delicate — males have elaborate thread-like fin extensions. Best in nano setups with peaceful micro fish or shrimp tanks. Stunning in well-planted tanks. Slow swimmer; shouldn't compete with boisterous fish for food.

Check the whole aquarium. Tank size alone does not establish compatibility. Confirm adult size, water overlap, social grouping, territory, diet, and the individual animals before stocking.

Check compatibility in Fishician