Bicolor blenny

Care at a glance

Overview

The bicolor blenny is a small, algae-grazing perching fish for a marine tank. It is easy to keep, as long as it stays well fed.

Caring for the bicolor blenny

Give a bicolor blenny a mature tank of at least 29 gal (110 L), with plenty of live rock and some algae growth. It perches and grazes on the bottom and rockwork, hopping among the rocks and ducking into holes. Rockwork matters more to it than open swimming space.

Hold stable marine water at 72 to 79°F (22 to 26°C) and a pH of 8.1 to 8.4. Feed a mostly herbivorous diet of marine and blue-green algae plus some meaty foods. The film algae it grazes from the rock adds to that.

Keep one male per tank, since bicolors quarrel with their own kind and with other small perching blennies. Toward unrelated fish they are mostly peaceful. They can still pick at other blennies, small gobies and dartfish, so choose tank mates with caution.

Treat it as reef safe with caution, and keep it well fed. In a large, well-fed reef it usually behaves. An underfed bicolor can nip clam mantles and pick at fleshy LPS polyps.

Breeding males can flush a bright orange-red across the back half of the body. Like most Ecsenius, it is only rarely bred in home aquariums, so trade stock is wild-caught.

Good to know

The bicolor blenny, Ecsenius bicolor, is a combtooth blenny in the family Blenniidae. As the name says, it is two-toned, with a bluish to brown front half shading into a dull orange or red rear half. Its colors vary and change with mood. It has the blunt-nosed face and eye cirri typical of the genus, and it grazes with fine, comb-like teeth.

In the wild

Bicolor blennies live on Indo-Pacific reefs from the Maldives and the eastern Indian Ocean to the western Pacific. They perch in rock crevices there and graze film algae off nearby surfaces.

Common questions

Related species

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