Blue assessor

The blue assessor (Assessor macneilli) is a small marine fish of the family Plesiopidae, native to reefs of the western Pacific, particularly around Australia and the Coral Sea. It has a deep blue body, sometimes with fine dark speckling, and swims in a characteristic head-down or inverted posture beneath ledges and inside caves. It is a peaceful, retiring fish that suits calm reef communities and can be kept singly or, in larger tanks, in small harem groups. It should not be housed with aggressive or boisterous species that would outcompete it. A reef aquarium with plenty of rockwork, overhangs, and caves and a tight lid is ideal, as it prefers shaded spaces and may jump. It feeds on zooplankton and accepts small meaty frozen foods such as mysis and enriched brine shrimp. Reef-safe with corals and invertebrates. It is a mouthbrooder that has been bred in captivity, the male incubating the eggs.