Blue Harlequin Rasbora

A form of the Harlequin Rasbora with a blue-tinged body and the usual black wedge. Mass-produced fish can be weaker than wild ones, so buy healthy stock.

Check the scientific name when buying, as common names vary between sellers and countries.

Mature females are usually rounder in the belly, and males are usually slimmer and often brighter.

A long tank with open swimming water, plants around the edges and steady filtration suits this fish. A darker substrate and some floating plants usually bring out its colour.

Active and social, and most settled when kept with its own kind.

Keep a group of at least 6, and more if you can. Larger groups are calmer and show better colour and behaviour.

Not territorial, although males may spar and display.

Suits a community of similar-sized, peaceful fish that like the same water. Avoid large predators, which will treat it as food. It may eat baby shrimp.

Fairly tolerant of different water, if it is clean and stable.

An omnivore that eats small invertebrates in the wild and readily takes small prepared foods.

Feed small amounts, and remove anything left after a few minutes.

Lays eggs on plants or in the substrate, depending on the species, and many keepers collect the eggs to raise separately. Some species have eggs that survive long dry periods.