The Polackorum Pencil Wrasse (Pseudojuloides polackorum) is a vibrant, slender marine fish from the southwestern Indian Ocean (South Africa to Kenya) known for its distinct coloration, peaceful nature, and suitability for reef aquariums, though it's an expert-level fish needing a sandy substrate to burrow and meaty foods, sometimes nipping small invertebrates. 

Key Characteristics:

Scientific Name: Pseudojuloides polackorum.

Common Names: African Pencil Wrasse, Polacks.

Appearance: Slender body with bright, iridescent markings and often a black caudal fin (tail).

Size: Males reach about 12.3 cm (5 inches). 

Aquarium Care:

Difficulty: Expert.

Tank Size: At least 50 gallons, with plenty of live rock for hiding.

Substrate: Requires a fine sand bed to burrow and sleep in.

Temperament: Peaceful but can nip at small shrimp and invertebrates, making it less reliably reef-safe.

Diet: Carnivorous, needs meaty foods like Mysis or brine shrimp.

Water Parameters: Standard marine parameters (temp 72-78°F, pH 8.1-8.4, Salinity 1.020-1.025). 

Habitat:

Native to subtropical reefs in the Western Indian Ocean, from South Africa to Kenya and

Madagascar.

Found in relatively shallow waters (5-20m).