Aquarium Livestock Pet Care Guides



Indo-Pacific and Caribbean

Tank Temperature




Specific Gravity



Omnivorous, but mostly carnivorous; small frozen and prepared foods, including brine shrimp, plankton, and mysis shrimp


Shy; peaceful; many are nocturnal; schooling; may eat ornamental crustaceans as adults; provide plenty of hiding places


Community and Coral Safe; Invert Safe, with caution; best kept in pairs or groups. Can be kept with docile tankmates. Use caution when housing with large Angels, Blennies, Damsels, Hogfish, Grunts/Sweetlips, Parrotfish, Pseudochromis/Dottybacks, Puffers, Squirrelfish, and larger Wrasses. Do not keep with Anglers, Groupers, Lionfish, Scorpionfish, Seahorses, Pipefish, or aggressive Triggers.

Species Overview

Cardinalfish are distributed throughout the world's tropical seas, mostly along reefs, but also in tidal pools and mangrove swamps. They are small fish that sport various colors and patterns, usually reds, browns and yellows. Perhaps their most distinguishing characteristic is their unusually large eyes, which allow them to see better at night as they search for small invertebrates and fishes to feed on. These little fish usually hide out for most of the day under overhangs and other shady areas of the reef.

In their native habitats, large groups of Cardinalfish school together. As juveniles in aquariums, Cardinalfish will peaceably school in your aquarium, but as they grow older dominant males begin to establish their pecking orders. Once a dominant male has chosen his mate, it is best to remove all but the pair. To avoid problems, it may be easier to stick with mated pairs in most aquariums, if you're able to distinguish male and female when you purchase them.

Cardinals require a diet of meat and vegetable foods and may be shy eaters. They accept just about any commercial food, but they may need a little time to acclimate to a new environment and may not eat during that period. Live brine shrimp may help to get them used to their new surroundings.

Overall, these species are quite hardy to keep in a home aquarium, making them popular among hobbyists. Many species of Cardinalfish are commonly available for the home aquarium. These fish make great additions to a peaceful aquarium, adapting well to life in captivity and quickly becoming favorites of aquarists.

We always suggest that you do further research before adding a new pet to your tank. What we have provided for you are guidelines and suggestions. If you have any further questions or concerns, please contact our fish room at 717-299-5691 ext. 1213 or

Recommended Items

Live Rock
Frozen Aquarium Foods
Freeze Dried Plankton