Bicolor Blenny Care Guide
Ecsenius bicolor · Saltwater Blenny
What Bicolor Blenny look like
The Bicolor Blenny (Ecsenius bicolor) exhibits a distinctive and striking coloration, characterized by a vibrant blue head that transitions into a bright yellow body. This species can reach a maximum adult size of approximately 4 inches (10 cm). Sexual dimorphism is subtle, with males typically displaying slightly more vibrant coloration and larger dorsal fins compared to females. A notable morphological feature is the elongated body shape, which is typical of blennies, along with a small, terminal mouth adapted for grazing. The species possesses a single dorsal fin that runs the length of the body, with the first few spines being elongated, contributing to its unique profile. Additionally, the Bicolor Blenny has a well-developed lateral line system, which aids in detecting water movements and potential predators.
Behavior & temperament
The Bicolor Blenny is known for its semi-aggressive temperament and territorial behavior, often establishing dominance within its habitat. It typically occupies the upper levels of the reef, where it can be seen perched on rocks or corals, ready to dart into crevices when threatened. Breeding behavior involves males establishing territories and engaging in courtship displays to attract females. During spawning, males will perform a series of rapid movements to entice females into their territory. This species is generally social, often found in small groups, but can exhibit aggressive behavior towards intruders, especially during breeding seasons.
Diet & feeding
In the wild, the Bicolor Blenny primarily feeds on algae, making it an obligate herbivore. In captivity, it requires a diet rich in marine algae, spirulina, and high-quality herbivore pellets to thrive.
Behind the name
The genus name 'Ecsenius' is derived from the Greek word 'eksenos', meaning 'strange' or 'unusual', while the species name 'bicolor' refers to its two distinct colors, blue and yellow.
Plan your tank
Check the numbers before you buy: tank volume, salinity, salt mix, water changes, and your ongoing care routine.
Keeping Bicolor Blenny?
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