Blue Velvet Damsel (Neoglyphidodon oxyodon)

The Blue Velvet Damsel (Neoglyphidodon oxyodon) is one of the most striking small fish in the hobby as a juvenile: a deep blue-black body with a velvety sheen, electric blue streaks scribbled across the face and flanks, and a bold white bar just behind the head. It is hardy, eats anything, and tolerates a wide range of conditions, which makes it tempting as an early addition to a marine tank. Two things are worth knowing before you buy, and both are covered below. Browse the rest of our saltwater livestock and supplies to build the reef around it.

Read This First

• The colors fade with age. That electric blue scribbling and the white bar are juvenile traits. As this fish matures it darkens toward a plain charcoal or brown-black, and most of the pattern disappears. Buy it because you like the fish, not only the photo, because the adult looks quite different.
• It gets bolder as it grows. Juveniles are unassuming. Adults are territorial and will defend a chosen patch of rock, harassing smaller or more timid tank mates. Plan the stocking around that rather than hoping it stays mellow.

Care Guide

• Tank size: 55 gallons or larger. It reaches about 6 inches and needs room to hold a territory without pressuring everything else in the tank.
• Water parameters: 72 to 78°F, pH 8.1 to 8.4, salinity 1.020 to 1.025, dKH 8 to 12. Genuinely forgiving, which is a large part of the appeal.
• Aquascape: plenty of rockwork with caves and line-of-sight breaks. Broken sight lines are the single most effective way to keep a territorial damsel civil.
• Feeding: omnivore with a real appetite for greens. Rotate a quality marine pellet with frozen foods such as PE Mysis and dried seaweed on a VeggieMag clip.
• Stocking order: add it last. Introducing a damsel to an established tank means it has no claimed ground when everyone else is already settled, which takes most of the heat out of the aggression.
• Reef safe: yes. It will not pick at corals, clams, or ornamental shrimp. The caution with this species is about fish, not invertebrates.

Specifications

Compatibility

Best kept with fish that can hold their own: tangs, larger wrasses, hawkfish, and other robust community fish in a tank with plenty of rock. The Bicolor Dottyback and Three Stripe Damselfish occupy the same feisty niche, so give them separate territories or skip the combination in a smaller tank. Avoid pairing it with shy, slow feeders such as firefish, small gobies, or mandarins, which tend to lose out at feeding time. Keep one per tank unless the system is large, since they do not tolerate their own kind. If you want the look without the attitude, the Blue Green Chromis is the peaceful shoaling alternative from the same family. All corals and ornamental invertebrates are safe.

Recommended Foods & Supplies

• Piscine Energetics PE Mysis frozen food
• Xtreme Marine PeeWee Pellets
• Vitalis Marine Grazing Pellets
• Ocean Nutrition Green Marine Algae dried seaweed
• Two Little Fishies VeggieMag seaweed clip

FAQ

Will it really lose the blue?
Yes. The electric blue markings and the white bar are juvenile colors, and they fade as the fish matures into a much darker, plainer adult. Some individuals keep a hint of blue in the right light, but do not buy one expecting the juvenile look to last.

Is it reef safe?
Completely, where corals and invertebrates are concerned. It will not nip corals, clams, or shrimp. The only compatibility question with this species is how it treats other fish.

Can I keep more than one?
Not in a normal-sized tank. They are intolerant of their own kind and will fight until one gives up. One per system is the safe rule.

How aggressive is it really?
Manageable with planning, difficult without it. In a 55 gallon or larger tank with good rockwork, robust tank mates, and the damsel added last, it is usually a bold but tolerable resident. In a small tank of peaceful fish it will run the show.