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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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Bristlenose Pleco

Bristlenose Pleco

Overview The Bristlenose Pleco (Ancistrus cf. cirrhosus) is the familiar bristlenose catfish sold in most stores. Males grow large fleshy bristles on the snout and head. Females may have a few small ones. Grows to about 5 in (13 cm) standard length, much smaller than...

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Cherry Barb

Cherry Barb

Overview The Cherry Barb (Puntius titteya) is a small, peaceful barb. Males turn deep cherry red. Endemic to the wet zone of southwestern Sri Lanka. Grows to about 2 in (5 cm) standard length. An excellent beginner fish. Almost all fish sold are farm-bred. Feeding...

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Common Pleco

Common Pleco

Overview "Common Pleco" is a trade name for several large suckermouth catfish, most often the Amazon sailfin catfish (Pterygoplichthys pardalis). Store fish may be a related species. Hypostomus plecostomus, a smaller fish from coastal rivers of the Guianas, is also...

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Otocinclus Catfish

Otocinclus Catfish

Overview "Otocinclus" or "oto" covers several small algae-eating catfish. The one sold most often is probably Otocinclus macrospilus. Shipments are often mixed species. O. macrospilus comes from the upper Amazon in Peru, and possibly Colombia and Ecuador. Grows to...

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Tinfoil Barb

Tinfoil Barb

Overview The Tinfoil Barb (Barbonymus schwanenfeldii) is a large, shiny silver barb with red fins. Native to Southeast Asia. Found in Thailand, Malaysia, Sumatra and Borneo. Grows to about 14 in (36 cm) standard length. It is sold small but grows fast. Feeding An...

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Scarlet Badis

Scarlet Badis

Overview The Scarlet Badis (Dario dario) is one of the smallest percoid fish. Males are bright red with blue bars. Found in tributaries of the Brahmaputra in West Bengal and Assam, India. Grows to about 0.8 in (2 cm) standard length. A popular nano fish. Feeding A...

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Sailfin Pleco

Sailfin Pleco

Overview The Sailfin Pleco (Pterygoplichthys gibbiceps) is a large suckermouth catfish with a tall dorsal fin and a leopard-like pattern. Native to the Amazon and Orinoco basins in Brazil, Ecuador, Peru and Venezuela. Can reach around 18–20 in (45–50 cm). Feeding An...

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Rosy Barb

Rosy Barb

Overview The Rosy Barb (Pethia conchonius) is a hardy barb. Males turn rose-red when in color. Widespread from Pakistan through India, Nepal and Bangladesh. Grows to about 3.9 in (10 cm) standard length. One of the hardiest small cyprinids. Long-finned and neon forms...

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