Microalgae. How we loathe it! It can cause reef aquarists great despair as it smothers their corals or makes a once-gorgeous reef tank look like an overgrown meadow. We try to avoid this by keeping phosphate and nitrate levels down (food for algae), adding herbivorous invertebrates (snails and hermit crabs) to reduce algae and also seeking the assistance of algae-eating fish (tangs and rabbitfish, among others). Members of these two fish families can help control algal growth, but they are large and need a lot of swimming room.

 

There is, however, another group of piscine herbivores that can be enlisted in the war on algae. These are the blennies (family Blenniidae). We will examine several of the most common blenny groups encountered by aquarists.

 

9 Fun Facts About the Blenny:

 

1. The giant blenny from the eastern Pacific is used in a soup that reportedly produces a slight intoxication of short duration.

 

2. The appendages scattered across a blenny’s head are called cirri and vary from simple stalks to feathery, multibranched tufts. Although a prominent feature on most blennies, the exact purpose of these structures is not known.

 

 

3. The Indo-Pacific’s hairtail blenny, which can reach 20 inches long, looks and behaves more like an eel.

 

 

4. The blenny is often mistakenly called “blemmy,” which is a mythological headless monster with a face implanted in its chest.

 

5. In the Caribbean, pikeblennies and sailfin blennies have evolved extremely large dorsal fins used in elaborate late-afternoon displays to attract females.

 

6. Many bottom-dwelling blennies lack swim bladders and have lost the ability to swim altogether.

 

7. Fangblennies from the Indo-Pacific have an intimidating pair of recurved canine teeth used for defense and territorial displays. Occasionally, divers hanging onto mooring lines become the victims of these terrifying two-inch brutes.

 

8. A blenny battle over territory or a mate can be a rip-roaring, jaws-locked affair lasting from seconds to hours.

 

 

9. Two species of fangblennies hang around cleaning stations mimicking the do-gooder cleaner wrasse. Unsuspecting client fish, hoping to have parasites removed, at times become the victims of sneak attacks that can remove chunks of skin.