Freshwater Aquarist

Popular Fish Species for your Aquarium

Here are some of the most popular freshwater fish species that are commonly kept in aquariums, each with unique characteristics and care requirements.

A common rule of thumb for how many freshwater fish you can keep in an aquarium is to allow about 1 inch of fish per gallon of water; however, this can vary depending on the specific fish species, their adult size, activity level, and bioload, with heavily planted or densely stocked tanks often needing more filtration and swimming room.

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Clown Knifefish

Clown Knifefish

Overview The Clown Knifefish (Chitala ornata) is a large, nocturnal predator with a row of black spots along its knife-shaped body. Native to the Mekong, Chao Phraya and Mae Klong basins of Thailand, Laos, Cambodia and Vietnam. Can reach about 39 in (100 cm), far too...

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Tiger Barb

Tiger Barb

Overview The Tiger Barb (Puntigrus tetrazona) is a bold, orange-and-black striped barb and a classic aquarium fish. Probably native to central and southern Sumatra. Grows to about 2.4 in (6 cm) standard length. Green, albino and other strains are common. Wild fish are...

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Serpae Tetra

Serpae Tetra

Overview The Serpae Tetra (Hyphessobrycon eques), also called the jewel or callistus tetra, is a red tetra with a black shoulder spot. Found through much of the Amazon and the Río Paraguay. Grows to about 1.6 in (4 cm) standard length. Feeding Likely omnivorous....

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