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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Bala Shark

Bala Shark

Overview The Bala Shark (Balantiocheilos melanopterus), also called the tricolor shark minnow, is a silver, black-edged cyprinid, not a true shark. Native to rivers and lakes of Borneo, Sumatra and Peninsular Malaysia. Grows to about 14 in (35 cm) standard length, so...

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Bolivian Ram

Bolivian Ram

Overview The Bolivian Ram (Mikrogeophagus altispinosus) is a peaceful dwarf cichlid. It is also sold as the Bolivian butterfly cichlid. Native to the upper Rio Madeira basin in Bolivia and Brazil. Grows to about 3.1 in (8 cm) standard length. Usually a better choice...

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Discus

Discus

Overview The Discus (Symphysodon aequifasciatus and related Symphysodon species) is a disc-shaped Amazon cichlid prized for its color. Wild fish live in slow tributaries and forest pools along the Rio Solimões and Amazon. Grows to about 6 in (15 cm) long and nearly as...

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German Blue Ram

German Blue Ram

Overview The German Blue Ram (Mikrogeophagus ramirezi), also called Ramirez's dwarf cichlid or butterfly cichlid, is a small, jewel-like dwarf cichlid. Native to the llanos savanna wetlands of the Orinoco basin in Venezuela and Colombia. Grows to about 1.6 in (4 cm)...

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Iridescent Shark

Iridescent Shark

Overview The Iridescent Shark (Pangasianodon hypophthalmus) is a large, schooling catfish, not a shark. It was formerly called Pangasius sutchi. Native to the Mekong and Chao Phraya rivers of Southeast Asia. Can reach about 51 in (130 cm) standard length. Sold as...

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White Cloud Mountain Minnow

White Cloud Mountain Minnow

Overview The White Cloud Mountain Minnow (Tanichthys albonubes) is a small coldwater cyprinid with a gold stripe and red fins. Named for White Cloud Mountain near Guangzhou, China. It is very rare in the wild. Grows to about 1.6 in (4 cm) standard length. Long-finned,...

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Siamese Algae Eater

Siamese Algae Eater

Overview The Siamese Algae Eater (Crossocheilus langei and close relatives, long sold as "C. siamensis") is a slim cyprinid with a black side stripe. Found in Borneo, Peninsular Malaysia, southern and western Thailand, and possibly Myanmar. Grows to about 6 in (15 cm)...

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