Filament glassfish, Gymnochanda filamentosa

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Matt Clarke explains how to keep the stunning Filament glassfish, Gymnochanda filamentosa.

Common name: Filament glassfish, Threadfin glassfish.

Scientific name: Gymnochanda filamentosa, Boeseman, 1957.

Origin: Indonesia and Malaysia. Recorded from Sungai Melawi and Kapuas in Borneo, and from southern Malaysia.

Size: Small at about 4cm long.

Diet: Glassfish don't usually take flake that readily, so offer these small live or frozen foods, such as Daphnia, Cyclops, microworm and bloodworm.

Water: While some glassfish are found in slightly brackish waters, this species is from the opposite – soft, acidic blackwaters.

That said, I've seen it kept successfully in harder water, and there are also reports of it surviving life in brackish aquaria. It may well be found in a range of habitats in nature. Go for a pH of 6-7, with a hardness of 1-8GH.

Aquarium: These are relatively shy and tricky to keep, so it's best to avoid them if you don't have prior experience with the more picky chandids. I'd go for a group of six or more in a quiet, densely planted aquarium.

Set this up either as a species tank or as a community containing a few small, peaceful tankmates that are unlikely to nip its long fins " blackwater rasboras would be ideal.

Females lack the blue-tipped filaments on their fins seen in males.

Previous imports of this species have often been made up almost entirely of male fish.

Notes: There are three species in the Gymnochanda genus: G. filamentosa, G. flamea and G. limi.

Availability: These are one of the most sought-after glassfishes and are very rarely seen for sale. They're starting to reappear in the trade after years of absence. These were spotted at Maidenhead Aquatics @ Oxford.

Price: These were on sale for £4 each.

This is an article from the Practical Fishkeeping website's archives. It may not be reproduced without written permission.