The Dwarf gourami, Colisa lalia, is a popular community fish that comes in a number of different colour forms.
Common name: Dwarf gourami, Red dwarf gourami, Striped dwarf gourami, Sunset dwarf gourami
Scientific name: Colisa lalia
Synonyms: This species has previously been known as Colisa lalius (a misspelling) and Trichopodus lalius (the original name). Others have suggested that the fish should actually now be called Trichogaster lalius or Polyacanthus lalius, but neither scientific name is considered valid at the moment, so we’re sticking with Colisa lalia.
Origin: Hardly any of these are wild caught these days – in fact, I’m pretty sure I’ve never seen wild Dwarf gouramis imported, as they are now farmed for the trade in a variety of colour forms. In nature, the species is found in south Asia from Bangladesh to Nepal, Pakistan and India, including the part of India which lies immediately north of Myanmar.
Size: Males can reach around 7-8cm/2-3″, with females remaining a little smaller.
Water: This fish lives in neutral or slightly soft acidic water in nature. However, since most are now captive-bred, they tend to do fine in harder, more alkaline conditions. Under most circumstances, there should not be any need to alter your water chemistry in order to keep Dwarf gouramis. They will even breed in harder water, but you might find that success in rearing the offspring is higher if you soften the water in the breeding tank.
Diet: Readily accepts flake foods, but should also be offered frozen foods, such as bloodworm and daphnia to keep it in top condition and help heighten coloration.
Aquarium: This is an ideal community fish and can be kept in most aquariums from about 60cm/24″ upwards. You should keep these fish in sexed pairs (one male and one female) as the species is pair-forming and territorial. They generally mix well with most fish, but can become a little waspish during courtship and may squabble with other gouramis during breeding. Their delicate trailing pelvic fins are prone to being nipped, so don’t keep them alongside anything with a tendency to bite the fins of other fish.
Sexing: Very easy. Males are very brightly colored, while females are generally grey-ish.
Breeding: This species is a bubble-nester and constructs a floating nest made from scraps of plant that it pulls off during the breeding season. The female lays floating eggs which the male guards for a few days. The fry is extremely small and it’s unlikely that any will survive unless you go to the trouble of breeding them in a special aquarium away from other fish.
One drawback to this species is that it seems particularly prone to bacterial infection and Nocardia or Fish TB-like disorders. It would be highly advisable to ensure that any fish you purchase are plump, colorful and feeding well, and completely free of sores or red marks before purchase. Treating the bacterial infections these fish tend to carry is often unsuccessful.
Some shops no longer stock this species as some suppliers seem unable to provide disease-resistant fish. If you’re able to find decent stock, they should be very easy to keep once you have them established in your aquarium.
[Note: Recent research, published in 2006, has shown that up to 22% of Dwarf gouramies exported from Singapore carry a Dwarf gourami Iridovirus (DGIV). This harmful disease is likely to be the cause of losses.]
Availability: This fish is readily available in several color forms from virtually every aquatic shop. The red form shown above is a selectively-bred variety. The original wild-type color variety has lots of metallic blue vertical bars and is probably more commonly seen than this variety.
These are often sold in pairs consisting of one brightly colored male and one drab female.