What is Aquarium fish?
'''Aquarium fish''' are [[fish]] used in [[Aquarium|aquariums]]. They can be [[Fresh water|freshwater]] or [[Salt water|saltwater]]. Some [[fish]], such as the [[betta]], can be aggressive. == List of aquarium fish == === Freshwater === ==== Goldfish ==== The [[goldfish]] (''Carassius auratus'') is a freshwater [[Actinopterygii|ray-finned fish]] in the family [[Cyprinidae]] of the order [[Cypriniformes]]. It is a great fish for [[Aquarium|aquariums]], and is one of the most popular aquarium fish. They have become an invasive pest in parts of [[North America]]. The average lifetime of a goldfish is ten to fifteen years. ==== Pike topminnow ==== The [[pike topminnow]] (''Belonesox belizanus'') is sometimes found in the [[aquarium]] trade, but it isn't an easy aquarium resident. ==== Green swordtail ==== The [[green swordtail]] (''Xiphophorus'' ''helleri'') is a freshwater aquarium [[fish]] in the family [[Poeciliidae]] of the order [[Cyprinodontiformes]]. Green swordtails are very popular in aquariums. ==== Pygmy sunfish ==== ''Elassoma'', the [[Pygmy sunfish|pygmy sunfishes]], are popular as [[aquarium]] fish because of the males' [[Iridescence|iridescent]] colors and fascinating breeding behaviors. [[Category:Aquarium fish| ]]