Threadfin glassfish

Care at a glance

Overview

Keep a group of at least six to eight in a tank of 60 litres or more at 23 to 27 C in soft, acidic water with a pH of 5.0 to 7.0. It is peaceful but easily outcompeted, so keep it in a species tank or with tiny, gentle blackwater fish. It rarely accepts dry flake, so it needs regular small live and frozen foods such as daphnia, cyclops, microworm and bloodworm. Stable, clean, gently flowing water suits it best.

In the wild

Threadfin glassfish live in soft, acidic, tea colored blackwater streams and peat swamps with dim light and dense plants. They are small, delicate, semi-transparent fish that stay in loose groups. Recreate their home with soft, acidic water, tannins from leaf litter or botanicals, subdued lighting and plenty of fine leaved and floating plants. They are shy and sensitive, so a calm, mature tank is important.

Good to know

Gymnochanda filamentosa is a small glassfish in the family Ambassidae, the Asiatic glassfishes. Mature males grow long, blue-tipped filament extensions on the dorsal and anal fins, while females stay plain and lack the streamers. The transparent body is an adaptation for staying hidden in open, dimly lit water.

Did you know

Only the males carry the trailing blue-tipped fin filaments that give the fish its name, and they show them off in gentle displays to rivals and females.

Related species

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