Tone basin

The Chinese false gudgeon, Abbottina rivularis, is a small bottom-dwelling cyprinid native to China, the Korean peninsula and southern Japan. It has been widely introduced elsewhere, including the Mekong and Salween basins, Taiwan, Turkmenistan and Kyrgyzstan, and is considered invasive. It has started to appear in the aquarium trade and should never be released into natural waters outside its native range.

Rhinogobius giurinus is a goby found through much of China, plus Taiwan, the Korean Peninsula, Japan and the Red and Pha river basins in Vietnam. It appears to exist in a number of forms that differ in colour pattern, morphology or both, and it is unclear whether all of them are conspecific. Newly-imported wild fish tend to be aggressive towards conspecifics, so unlike most Rhinogobius it is best kept in sexed pairs.

The barbel steed, Hemibarbus labeo, is a cyprinid widespread in eastern Asia between the Yangtze and Amur river basins. A predominantly riverine fish of clear, well-oxygenated running water, it forms schools just above the substrate as an adult, and some populations make annual spawning migrations. Adults lack dark spots on the body and have a long snout and well-developed lips.