Bicolor Blenny

About

The bicolor blenny (Ecsenius bicolor) is one of the more personable small fish you can add to a reef tank, and its appearance makes it easy to identify. The front half of the body is a deep blue-grey while the rear fades into orange or yellow, a division that's hard to miss even across the tank. In the wild it ranges widely across the Indo-Pacific, from the Maldives out through Micronesia to the Phoenix Islands, where it inhabits clear lagoon and seaward reef zones with plenty of algae-covered rock and coral rubble. It's a confirmed grazer, spending most of its day picking at algae and biofilm, which makes live rock essential for its long-term wellbeing. Behaviorally it's among the gentler blennies. Genuinely timid with other species rather than the scrappy personality some blennies carry. It will quickly claim a hole or crevice as its own retreat, and will often sit with just its head poking out when something startles it. Over time it tends to become quite comfortable with its tankmates, occasionally tagging along as they move around the tank. One caveat: it has a habit of deciding that a feather duster or tube worm makes a more appealing home than the rockwork, so keep that in mind before adding one to a mixed invert setup.