Huong

Macropodus erythropterus is a paradisefish from coastal hill streams of central Vietnam, in Quang Binh and Quang Tri provinces. Occasionally traded, sometimes as 'red-backed paradisefish', it is often misidentified as M. spechti, which lacks red in the dorsal, anal and caudal fins. Whether the two represent the same taxon has been debated. A bubble nester, it is relatively peaceful unless breeding.

The black paradise fish, Macropodus spechti, is a labyrinth fish from central Vietnam, known with certainty from the Thu Bồn and Hương river systems. Its name is frequently misapplied to the similar-looking M. erythropterus, easily identified by reddish pigmentation in the dorsal, anal and caudal fins. Older literature sometimes refers to it as M. concolor. Relatively peaceful unless breeding, it is kept in pairs.

Micronemacheilus cruciatus is a small nemacheilid loach that appears to be endemic to the coastal rivers of Vietnam. It is traded under names including 'Vietnamese multi-banded zebra loach' and 'hovering zebra loach', and its colour pattern is a dark lateral stripe with numerous vertical cross-bars. It can be susceptible to swings in water chemistry and should not go into a biologically immature aquarium.

The tiger hillstream loach, Sewellia lineolata, is a gastromyzontid loach from fast-flowing headwaters in Vietnam and on the Mekong in Laos. Three to five dark stripes on the body make it difficult to confuse with any other member of the genus. The water must be clean, fast-flowing and well-oxygenated, and Sewellia species are arguably the easiest of all loaches to breed in aquaria.