Chaetobranchus flavescens

Chaetobranchus flavescens is one of the most unusual cichlids in the hobby — a filter-feeder from the Amazon basin whose gill rakers are highly modified to strain microorganisms and plankton from the water column, analogous to the feeding strategy seen in some whale sharks and manta rays. This adaptation makes it entirely unique among cichlids.

In the aquarium, Chaetobranchus will filter-feed on phytoplankton-rich green water and very fine suspended foods, but will also accept fine-grained prepared foods and microplankton supplements. Standard large cichlid pellets alone are inadequate for this species. A green water culture or regular addition of liquid invertebrate food is essential.

This is a rare and scientifically fascinating fish for the specialist aquarist who appreciates unusual cichlid biology. Despite their gentle temperament and peaceful nature, their complex feeding requirements make them unsuitable for general community keeping.

Water: Temperature 25–29°C, pH 5.5–7.0, GH 1–10, KH 1–5; excellent water quality; some green water algae supplementation beneficial. Tank: 300 L minimum; gentle to moderate flow; avoid powerful currents that prevent natural filter-feeding behaviour. Feeding: Liquid invertebrate food, phyto/zooplankton supplements, finely ground cichlid pellets, and green water; feed small amounts multiple times daily. Breeding: Very rarely bred in captivity; open spawner if appropriate conditions are met; fry require infusoria and microplankton. Compatibility: Peaceful with similarly sized South American cichlids; avoid boisterous competitors that may outcompete at feeding time.