Species description

Care, breeding and tankmates

Fish profile

Temperament

Peaceful

They are peaceful, highly inquisitive, and boast an array of comical behaviors. They often sit on a preferred rock ledge and survey their surroundings with independently moving eyes. Once they establish their territory, they become quite bold and visible throughout the day.

Diet

Herbivore

This species primarily grazes on microalgae and diatom films found on live rock and tank glass. A diet rich in vegetable matter is essential, including spirulina flakes, dried seaweed, and herbivore-specific pellets. They will sometimes accept small meaty foods like mysis, but these should be fed sparingly.

Sex ratio

Solitary

It is best practice to keep a single Bluebelly blenny per aquarium to prevent severe conspecific aggression. Males are highly territorial and will combat each other fiercely for dominant rockwork positions. A bonded pair can be kept together, but establishing one is difficult.

Feeding frequency

Twice daily

Because they constantly pick at algae all day, direct feedings of supplemental foods should occur once or twice daily. Providing a constant grazing source, such as a nori clip, helps satisfy their continuous metabolic needs. Frequent small meals ensure they remain plump and brightly colored.

Bioload

The Bluebelly blenny introduces a very minimal bioload, making it a great addition to almost any reef aquarium. Its waste production is easily mitigated by standard filtration and a regular maintenance schedule. It is highly suitable for nano aquariums due to its small adult size.

Flow

Moderate

They enjoy moderate water flow, which encourages the natural growth of their preferred microalgae. Good flow mimics the natural reef surge zones where they are commonly found. They will typically find a small crevice to retreat into if the current becomes overwhelming.

Jump risk

Yes

Like most blennies, they possess a strong flight response and will readily jump from an open aquarium. A tight-fitting lid or mesh screen is absolutely vital for their safety. Care must be taken not to spook them during tank cleaning or rapid lighting changes.

Reproduction

Oviparous

They are demersal cave spawners; the female deposits eggs in a secure crevice which the male then guards aggressively. The male will fan the eggs to provide oxygen and keep them free of debris until they hatch. The resulting fry are extremely small and notoriously difficult to raise in captivity.

Compatibility & tankmates

Reef safe

It is exceptionally peaceful and poses no threat to corals, clams, or ornamental invertebrates. It is an ideal resident for community tanks housing other small, docile species. Caution is only required when keeping it with other bottom-dwelling gobies or blennies that might compete for territory.

Tank level

Bottom

They are strictly benthic fish that perch on live rock and hop along the substrate. Lacking a swim bladder, they do not swim in the open water column. They require a complex rockwork structure with many small holes to provide ample hiding spots.