Indian Mud Moray

Gymnothorax polyuranodon is exceptional among morays for its broad salinity tolerance, occurring in fully freshwater rivers, lakes, brackish estuaries, and coastal marine environments across South and Southeast Asia. Large adults display a complex pattern of dark brown and pale mottling that provides excellent camouflage among river debris.

This is a large, powerful species that demands a very substantial aquarium with exceptional escape-proofing: morays can push through surprisingly small gaps and exert considerable force on lid fittings. Deep cave structures are essential, and rockwork should be stable and unable to be displaced.

Feeding involves meaty foods: whole prawns, mussel, silverside, squid, and frozen fish flesh. Live feeder fish are not recommended. Due to its large adult size and aggressive feeding behaviour, this species is best housed alone or with very large, robust tankmates in a dedicated predator setup.

Water: Fresh to brackish, pH 7.0–8.0, temperature 24–28°C, GH 5–18, KH 3–12. Tank: Minimum 350 L, very robust sealed lid, heavy rockwork caves, powerful filtration. Feeding: Carnivore; whole prawns, mussel, silverside, squid, and frozen fish flesh. Breeding: Not recorded in captivity; presumed marine spawner. Compatibility: Species tank recommended; only very large robust fish otherwise.