Sông Cái

The Chinese snakehead, Channa asiatica, is a snakehead native to central and southern China and northern Vietnam. One of several Channa lacking pelvic fins, it is told apart from them by vertical black bars on a brownish body and numerous white spots on the body and fins. It is best kept in a species tank. Pairs build no bubble nest, and both parents defend several thousand floating eggs and the fry.

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.

Schistura callichromus is a nemacheilid loach recorded only from the Babianjiang River in the Red River basin, Yunnan Province, China. It is expected to occur in Vietnamese waters as well, and Kottelat (2012) amended the spelling of its name to 'callichroma'. Wild specimens have been observed living in social aggregations of up to six in clear, well-oxygenated headwater streams.

Schistura laterivittata is a nemacheilid loach recorded only from the Babianjiang River in the Red River basin, Yunnan Province, China. Most recent authors have treated it as a synonym of S. caudofurca, but this appears to be a case of misidentification: S. caudofurca has a deeply forked caudal-fin and no dark lateral body stripe. It is expected to occur in Vietnamese waters as well.