Species description

Care, breeding and tankmates

Fish profile

Temperament

Semi-aggressive

The Chestnut Eyelash Blenny is active, alert, and peaceful but territorial. They occupy the lower sections of the tank, perching on rocks and darting around using their pectoral fins. They possess a curious and highly personable nature, often observing activity outside the tank.

Diet

Herbivore

This species is primarily herbivorous, feeding on microalgae and detritus by grazing on rocky surfaces. In captivity, they must be provided with plenty of natural algae to graze on. Supplement their diet with high-quality spirulina flakes, algae wafers, nori sheets, and occasional small portions of frozen foods.

Sex ratio

Solitary

Solitary

Feeding frequency

Twice daily

They should be fed once or twice daily with supplemental vegetable matter if natural algae in the aquarium is scarce. In a mature reef tank with abundant algal growth, they will graze continuously throughout the day. Frequent feeding checks are important to ensure they maintain a rounded belly.

Bioload

The chestnut blenny exerts a moderate bioload on the marine aquarium system, largely dependent on its continuous grazing behavior. As an active herbivore and detritivore, it constantly consumes microalgae and expels a steady stream of waste, though this is generally well-handled by typical reef filtration. Supplemental feedings of algae-based foods can slightly increase its waste production if not fully consumed. Maintaining an efficient clean-up crew and good water flow will easily offset its bioload impact.

Flow

Moderate

They prefer moderate to strong water flow, which reflects their native shallow reef and intertidal habitats. Good water movement helps simulate the surge zones they inhabit and keeps algae-grazing sites clean. High oxygenation is also vital for this active, bottom-dwelling species.

Jump risk

Yes

Blennies are notorious for being exceptional jumpers, and the chestnut blenny is no exception to this rule. They are easily spooked by sudden movements, lighting changes, or aggressive tank mates, which can trigger a leap out of the water. Therefore, a tightly fitted lid or a custom mesh screen is absolutely necessary to keep them securely inside the aquarium. Even gaps around filter outputs or wiring should be carefully sealed to prevent escape.

Reproduction

Oviparous

They are oviparous with demersal spawning, where adhesive eggs are deposited into small rock crevices or empty shells. The male assumes the role of guarding and fanning the nest until the larvae hatch. Successfully breeding them in home aquariums is highly challenging due to the difficulty of raising the planktonic larvae.

Compatibility & tankmates

Reef safe

They are peaceful and reef-safe, making them excellent community fish. However, they can show territorial behavior toward other blennies or species with a similar appearance that compete for grazing space. Provide plenty of rockwork to allow territory definition and keep only one per tank.

Tank level

Middle/Bottom

This species is a classic benthic dweller that spends nearly all of its time navigating the live rock structure in the lower to middle tiers of the tank. They utilize small crevices and holes as safe retreats, darting out to graze on nearby algae. You will rarely see them swimming in the open upper areas, as they heavily depend on the physical security of the hardscape. Their activity is almost entirely confined to the bottom and mid-level rockwork surfaces.