Dwarf anchor catfish

Probably the smallest species on today’s list, the Asian stone catfish, or Dwarf anchor catfish, is a wonderful (if somewhat inactive) addition to a well maintained nano tank.

These guys hail from the Indian subcontinent, where they are often found in large groups in slow moving bodies of water. Lucky to get much bigger than 2.5cm they offer up an option for something dinky that accepts a broad hardness and pH range — as is often found with Indian species.

Best kept in decent sized congregations, with plenty of hiding places and a soft substrate, my personal experience is that they tend to be more active in lower light or after dark, which is something to note if you want to watch them feeding.

A broad, carnivorous diet with plenty of little live critters like Cyclops is the recipe for success. They do seem to be extremely sensitive to any and all water quality issues, and as such I would avoid keeping them in the smallest sizes of tank, and instead aim for something a little larger. 50 or 60-litres and above would be much more stable than a tiny set-up.

Note that they don’t fare well in low oxygen conditions. The flowing, cool rivers they inhabit in the wild are awash with dissolved gases, and this needs to be replicated in the home tank. Plenty of surface turnover, additional airpumps and slightly cooler than usual conditions will all help here.