While sharks are undoubtedly head-turning captives, relatively few species are appropriate for home aquariums. Epaulette sharks, wobbegongs and cat sharks are among those who adapt best to captivity and remain a manageable size. In most cases, you can keep these species in aquariums with 180- to 300-gallon capacities. While nurse sharks are often stocked by retailers and they tend to thrive in captivity, they grow too large for most hobbyists.
Epaulette sharks (Hemiscyllium ocellatum) are elongate fish, with eel-like bodies and very flexible pectoral fins. This flexibility has allowed epaulette sharks to develop a locomotor style that resembles walking, in which they propel themselves across the bottom of the ocean by using their pectoral fins. Epaulette sharks use this unusual ability to crawl through tight rock crevices. They can even crawl out of the water to reach isolated tidal pools, where they can dine on trapped creatures. The ability to tolerate water with low oxygen content helps them survive in these tiny pools.
Epaulette sharks derive their name from the large black spots that adorn their sides, which may serve to dissuade predators. Popular among aquarists because of their small size, epaulette sharks rarely exceed 42 inches in length.
Wobbegongs are some of the most unusual sharks in the world. They have flattened bodies and incredibly intricate color patterns; a few species bear fleshy appendages that further help camouflage the stealthy predators. While several of the eight described species grow too large for home aquariums, Cobbler’s wobbegongs (Sudorectus tentaculatus), dwarf ornate wobbegongs (Orectolobus ornatus) and Ward’s wobbegongs (Orectolobus wardi) remain small enough for aquariums with 200 to 300 gallons of capacity.
Wobbegongs are voracious eaters, and they will attempt to eat most other fish which whom they are housed. In some cases, they may even attempt to eat fish approaching their own size. They rarely digest such large prey items completely; ultimately vomiting the undigested portion of the meal several days later.
Cat sharks are attractive critters, but their nocturnal habits cause them to spend the bulk of their days hiding in rock crevices. However, after the tank’s lights turn off, cat sharks come alive, prowling the tank for fish and small invertebrates. Many cat shark species bear very attractive markings and colors, which, combined with the small size of some species, make them popular among hobbyists. Some researchers, retailers and hobbyists refer to catsharks as “bamboo sharks.”
The cat shark lineage is quite robust, and scientists have described more than 100 living species. The most common catshark in captivity is the coral catshark (Atelomycterus marmoratus).
While nurse sharks (Ginglymostoma cirratum) often make splendid captives and adjust quickly to life in an aquarium, they grow too large for most aquarists. Nurse sharks may approach 9 feet in length, necessitating a truly massive tank consisting of several thousand gallons of water. It is illegal and inadvisable to release a nurse shark into the ocean, and the local aquarium is not going to accept your nurse shark once he outgrows your home, so you are best served by avoiding the acquisition in the first place.