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Threadfin Rainbowfish

Iriatherina werneri

Threadfin Rainbowfish (Iriatherina werneri) is a schooling community species for a cycled 20+ gallon freshwater aquarium. Plan for about 2 inches as an adult, 76-82°F water, pH 5.8-7.5, and moderate care. Keep a group of at least 6; larger groups often behave more naturally when the tank has room.

FlashyModerate care
Threadfin Rainbowfish, a flashy 2 inch aquarium species for 20+ gallon tanks
20 galMinimum tank
2 inAdult size
6Schooling minimum
76-82°FTemperature

Water Range

pH
5.8-7.5
GH
2-12 dGH
KH
1-8 dKH

Behavior

Temperament
Peaceful
Fin nipping
0/5
Territory
0/5

Diet and Care

Diet
omnivore/micro-predator
Diet difficulty
3/5
Care difficulty
3/5

Planning Notes

Moderate care needs; may require mature grazing surfaces or supplemental fresh/frozen foods.

This species may need live, frozen, fresh, or otherwise specialized foods.

live or fresh foodsmall foodsgentle flowfry predatorsafe with adult shrimp

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