Shark Fish

In this section of the site you find articles about true sharks (see articles below) and "freshwater sharks". When you purchase so called freshwater sharks from your local fish store, they are usually not sharks. Several types of small and silvery shark-like fish species are marketed as freshwater sharks even though they only have a body form that resembles that of a shark. There are true shark species that lives in freshwater, particularly in Australia, but these true sharks are not recommended for hobby aquarists. They will grow very large and you will need a huge aquarium if you want to provide them with a good home. Several species are also endangered and should not be removed from their natural environment unless needed for conservatory reasons, e.g. for a public aquarium. A majority of the most well known true shark species, such as the Great White shark and Hammerhead shark, are marine species.

There are also a few true shark species that can live in brackish waters and the Bull Shark can even leave the ocean and migrate several miles up in freshwater rivers and into lakes. The Bull Shark will usually do well in captivity, but due to its size it is only kept in public aquariums. It can reach a length of 3.5 meters and require plenty of space to thrive. It is also included in the IUCN Red List of Threatened Species and considered near threatened by CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora).

As mentioned earlier, the so called freshwater shark species are actually a better choice for a freshwater aquarium than the true freshwater shark species. If you have a saltwater aquarium you can also keep some of the smallest saltwater shark species. A saltwater aquarium is not suitable as a first aquarium; it is advisable to begin with a freshwater aquarium and gain some experience before you venture into the beautiful but somewhat more complicated saltwater world.

It is common for the so called freshwater sharks to come from rivers and lakes in Asia. They might look like sharks, but their anatomy and habits are very different from those of a true shark. The so called sharks are typically not even predatory. Always try to find out the true name of the “Shark” that you are offered in the fish store, since you should choose a species that will not outgrow your aquarium.

The Bala shark is one example of a so called shark that is commonly sold to hobby aquarists even though it will reach a mature size of 36 centimeters (14 inches) which makes it too big for a majority of the hobby aquarists. The Bala shark should also ideally be kept in a school consisting of at least six Bala sharks, since Bala sharks always form schools in the wild. Keeping six fishes that are longer than 30 centimeters in the same aquarium is unfeasible for most aquarists. The Black shark is another so called shark that is typically offered to aquarists when it is 5 centimeters (2 inches) long, and many fish stores are quite reluctant to tell the purchaser that the quite little fish that they just bought can become 82 centimeters (32 inches) long.