Mirabilis Eartheater

Geophagus mirabilis is a robust eartheater from the lower Amazon and Tocantins river systems of Brazil. It inhabits sandy marginal zones of large river channels and oxbow lakes. Adults develop striking orange-tipped dorsal and caudal fins and vivid blue-green iridescent cheek patches. Like all Geophagus, it is a continuous sand sifter, processing mouthfuls of substrate to extract invertebrates and organic detritus. Compared to many eartheaters it tolerates moderately harder and slightly alkaline water, broadening its suitability for hobbyists with average tap water. Provide a fine sand base of at least 5 cm depth, open swimming areas, and some driftwood. Keep in groups of five or more to distribute aggression and encourage natural social behaviour during spawning.

Water: Soft to moderately hard; pH 6.0–7.5, temperature 24–29 °C. Tank: 250 L minimum; fine sand substrate, open swimming areas. Feeding: Sinking pellets, frozen foods, occasional live bloodworm. Breeding: Delayed mouthbrooder; group spawning preferred. Compatibility: Peaceful with large tetras, peaceful catfish, and other eartheaters.