Sankey Dottyback

The Sankey dottyback is recognized by the distinct white stripes running from snout to tail along its slender black body; its back and belly are white and its dorsal fin is largely transparent. This striped pattern resembles the juveniles of the coral catfish (Plotosus lineatus). It is known as one of the most peaceful dottybacks; it is considered even more compatible than calm species such as the orchid dottyback (Pseudochromis fridmani).

A large share of the specimens in stores are aquarium-bred. Captive-bred specimens take to dry food immediately, are disease-resistant and suit a beginner's reef aquarium. Still, it is a dottyback: it may hunt small shrimp that fit in its mouth.

It lives under rock and coral overhangs and in caves in the southern Red Sea, the Gulf of Aden, Djibouti and the Socotra Archipelago. It is usually found in colonies among hard coral communities at depths of 2–10 meters. It stands out among dottybacks for living in groups.

• Volume: 75 liters is enough for a single specimen; at least 110 liters for a small group.
• Water: Salinity specific gravity 1.023–1.026, pH 8.1–8.4, temperature 24–27°C.
• Layout: Plenty of caves, crevices and rock overhangs; a complex rock structure where each individual can find its own hiding place.
• Reef compatibility: It leaves corals alone. It may hunt small shrimp such as sexy shrimp; there is usually no problem with larger shrimp such as cleaner shrimp. It reduces the number of bristle worms.
• Lid: Dottybacks can jump; a lid is recommended.

Carnivorous. Frozen mysis, brine shrimp, copepods and quality granules should be the staple. Captive-bred specimens accept granules immediately. Feed small amounts twice a day; vary the diet with enriched frozen foods to maintain color.

Calm for a dottyback. It guards the area around its own cave, but it does not chase other fish constantly. It can be more territorial towards similarly shaped, cave-dwelling species.

Good companions: Clownfish, chromis, gobies, blennies, cardinalfish, dwarf angelfish, tangs, cleaner shrimp.

Avoid: Sexy shrimp and small ornamental shrimp, other dottybacks (in a small aquarium), species that share the same cave-dwelling lifestyle such as the royal gramma, large predators.

It is one of the rare dottybacks that can be kept in a group. To form a group, 3–5 juveniles should be added at the same time and plenty of hiding places provided. Adding individuals to the group later leads to fighting. In a small aquarium a single specimen or a pair is safer.

The female lays a ball of eggs in a nest the male has prepared in a cavity; the male guards the eggs until they hatch. It is one of the species bred commercially; raising the planktonic fry requires rotifer and copepod cultures.

• Captive-bred specimens are very hardy.
• Marine white spot and velvet: Quarantine new fish for 3–4 weeks.
• If an individual within the group is constantly chased, separate it; stress makes it vulnerable to disease.

There is no reliable external difference. Dottybacks can start as females and change into males; the largest and most dominant individual in the group is usually the male.