Orbiculate Cardinalfish
The lesser-known sibling of the popular Pajama Cardinalfish, sharing the same chunky, round-bodied build, but patterned with a thin dark 'waistband' and scattered dark spots toward the tail rather than orange polka-dots. It is just as hardy and easy-going, settles well in a small same-species group, and is genuinely nocturnal — mostly hidden by day, feeding on plankton and small invertebrates from dusk onward. Reef-safe with corals, but as an opportunistic night hunter it will pick off very small ornamental shrimp and other tiny invertebrates given the chance.
Tankmates
How Orbiculate Cardinalfish gets on with the rest of the reef, checked pair by pair by the same engine as the live pre-flight.
Best kept apart
A real clash — aggression, predation or a same-genus fight.
Keep an eye on these
Usually fine, but worth watching in a smaller tank.
Good tankmates
No conflicts — a few popular ones to start with.
