Indian Glassfish

The Indian glassfish is so transparent that its spine, bones and silvery swim bladder can be seen through its body. It has a slight yellowish sheen; the edges of the males' dorsal and anal fins are bright blue. It is a calm, somewhat shy schooling fish.

Ethical warning: The trade sometimes sells glassfish that have had colored dye injected under the skin or have been dyed ("disco," "painted glassfish"). This procedure harms the fish and shortens its life; the dye fades over time. Do not buy these fish; choose naturally colored ones.

It lives in the still and slow-flowing waters, ponds, floodplains and vegetated banks of South and Southeast Asia. Some populations move down into slightly brackish waters near the coast.

• Volume: at least 80 liters and 80 cm length for a group of 6–10.
• Water: moderately hard to hard, slightly alkaline water; it does well in fresh water. A little salt is not essential, but it likes hard water.
• Decor: densely planted edges and roots; the fish is bolder when it has places to hide.
• Flow: gentle to moderate.

Carnivorous. Frozen bloodworms, brine shrimp, daphnia, cyclops and mysis. Most individuals eventually accept small granules and flakes as well, but on dry food alone their color and health decline.

Peaceful, shy and attached to its school. Males form small territories among themselves; they display with spread fins but do no harm. It may lose out to fast fish at feeding time.

Good companions: calm species of similar size: rasboras, calm barbs, rainbowfish, mollies, Corydoras, otocinclus.

Avoid: aggressive and fast-eating species, fin-nipping barbs, large predators.

A school of at least 6, ideally 10. When kept in small numbers it becomes timid and hides constantly.

It spawns among fine-leaved plants or moss in the morning hours. The parents provide no care. The fry are very small and in the first days take only moving, tiny live food (infusoria, rotifers), which makes raising them difficult.

• White spot and bacterial infections: common when stressed.
• Short lifespan in dyed fish: injection wounds are prone to infection.
• Starvation: in competitive aquariums.

Males have bright blue edges on the dorsal and anal fins and a more yellowish body. Females are silvery, without blue edges. Held against the light, the rear end of the female's swim bladder can be seen to be more rounded.