The Roughead Blenny is hands down our favorite blenny, and one of our favorite fishes overall. These are sexually dimorphic, with the females being yellow, and the males being a darker gray/black. These little guys hide in the tiniest of holes and dart out, grab food, and scoot back into their holes, tail first. They do this in the blink of an eye. They are perfect for a nano reef environment. Very common to see just their heads and their eyes shifting back and forth. They have fantastic personalities. They are a tiny fish though, as they only reach about 1.5" in total length.