The Bicolor Blenny (Ecsenius bicolor) is a colorful, entertaining marine fish known for its two-tone appearance, curious personality and habit of perching among the rockwork.

With a dark blue-brown front half transitioning into a bright orange or yellow-orange rear, the Bicolor Blenny adds plenty of character without requiring the space of larger marine fish. They're often seen peeking out from caves, hopping between rocks and grazing on algae throughout the aquarium.

Generally hardy and relatively easy to care for, the Bicolor Blenny can be a great choice for newer saltwater aquarists with an established, appropriately sized aquarium.

Quarantined Before Shipping

This fish undergoes quarantine, observation and preparation before shipment.

Depending on where the individual fish is within the quarantine process when your order is placed, additional time may be required before it is cleared for delivery.

Please allow up to 14 days for quarantine and preparation prior to shipment.

Once cleared, your fish will be scheduled for overnight delivery. The quarantine period occurs before shipment and is separate from carrier transit time.

Pre-shipment quarantine provides an additional period of observation and preparation, but aquarists may still choose to follow their own quarantine protocol before introducing new livestock into an established display aquarium.

Care Requirements

Scientific Name: Ecsenius bicolor
Common Name: Bicolor Blenny / Two-Colored Blenny
Care Level: Easy
Temperament: Generally Peaceful
Diet: Primarily Herbivorous
Minimum Aquarium Size: 30 Gallons
Reef Compatibility: Reef Safe With Caution
Aquarium Type: Marine / Reef
Recommended Quantity: One per aquarium unless compatibility and available territory are carefully considered

A 30-gallon minimum is commonly recommended, with plenty of established rockwork for grazing, hiding and perching.

Aquarium Setup

The Bicolor Blenny does best in an established saltwater aquarium with plenty of live rock, caves and crevices.

Rockwork serves multiple purposes for this species, providing secure hiding places, favorite perching spots and surfaces where the blenny can naturally graze.

Although generally peaceful toward other community fish, Bicolor Blennies can become territorial toward other blennies and similarly shaped fish. Keeping multiple Bicolor Blennies together is not recommended for the typical home aquarium.

Reef Compatibility

Reef Safe With Caution

Bicolor Blennies are commonly maintained successfully in reef aquariums and typically spend their time grazing on rockwork rather than bothering corals.

However, individual behavior varies. Underfed specimens have been reported to nip at clam mantles and fleshy LPS corals, so adequate nutrition and natural grazing opportunities are important.

Feeding

The Bicolor Blenny naturally grazes on algae growing throughout established rockwork and aquarium surfaces.

Its diet should also be supplemented with quality foods containing marine algae and spirulina, along with appropriately sized prepared marine foods. Natural algae should not be assumed to provide the fish's complete diet indefinitely.

A varied diet helps maintain body condition while reducing the likelihood of undesirable grazing behavior.

Personality

This is one of those little fish that can quickly develop a big personality.

Bicolor Blennies frequently choose a favorite cave or hole in the rockwork and spend their time darting between hiding places, perching on rocks and watching activity around the aquarium.

They're an excellent option for aquarists looking for a smaller marine fish that's interesting to watch even when it isn't cruising around the entire tank.

Appearance & Livestock Variation

Photos are representative of the species.

Because each fish is unique, size, coloration, markings and overall appearance will naturally vary between individuals. Exact coloration shown in product photography is not guaranteed.

Live Animal Shipping

$39.99 Overnight Live Animal Shipping Fee Per Order

Live fish and invertebrates ship Monday through Wednesday via FedEx Priority Overnight after completing applicable quarantine and preparation.

The live-animal shipping fee applies once per qualifying order, not once per animal.

Weather, unsafe temperatures or carrier conditions may result in shipment being delayed when necessary to protect livestock.

Tracking information will be provided once your order ships.

Please Note: Quarantine and preparation occur before shipment. Overnight shipping begins only after the fish has been cleared and scheduled for delivery.

Live Arrival & Health Guarantee

Your Bicolor Blenny is covered by the Infinity and Beyond Aquatics Live Animal Arrival & Health Guarantee Policy.

Live animals are guaranteed to arrive alive when delivery, acclimation and all applicable policy requirements are followed.

In the event of a DOA, contact Infinity and Beyond Aquatics immediately upon delivery and provide the required photographs and documentation according to our current policy.

After delivery, livestock health is influenced by acclimation, aquarium conditions, water quality, compatibility, nutrition and husbandry. Please review the complete Live Animal Arrival & Health Guarantee Policy before ordering for current eligibility requirements, claim procedures and exclusions.

Before Ordering

Provide an established aquarium of at least 30 gallons with plenty of rockwork, hiding spaces and grazing surfaces.

While generally peaceful, Bicolor Blennies may become territorial toward other blennies and similarly shaped fish. For most home aquariums, keeping a single Bicolor Blenny is recommended.

Why Buy From Infinity and Beyond Aquatics?

Infinity and Beyond Aquatics offers carefully selected marine livestock with clear information about care, compatibility and husbandry.

Applicable marine fish undergo quarantine and preparation before shipment, providing an additional period of observation before beginning their overnight journey to your aquarium.