Three Spotted Dwarf Rasbora

Care

The miniscule Three Spotted Dwarf Rasbora is restricted to parts of the Mekong basin in north-eastern Thailand where it is known from heavily vegetated marshes, ponds, and swamps with clear, relatively deep waters; although this species is said to exist in Laos, details of Laotian populations are somewhat sketchy. The Three Spotted Dwarf Rasbora may not be as brightly adorned as some of its close relatives, but it has a subtle beauty and is still a sought-after species for planted nano-tank enthusiasts. The aquarium must be mature and have myriad of hiding places amongst driftwood and thick vegetation, which should include floating species to help diffuse the light. Filtration should be good but water movement gentle. These peaceful shoaling fish can be rather timid, so a decent sized group of 12 or more will help them to feel more secure. A larger group will also result in a more effective, natural-looking shoal, with males displaying interesting behaviour as they compete with one another for female attention. Tankmates, if desired, must also be small and peaceable; for example, small Caridina and Neocaridina shrimp, Kuhli loaches (Pangio spp.), Sparkling gouramis (Trichopsis pumila), Otocinclus catfish, pygmy Corydoras spp., Danionella spp., Eirmotus octozona, Trigonostigma spp., and Blue Eyes (Pseudomugil spp.) could all be considered suitable. Much attention must be paid to water quality since Three Spotted Dwarf Rasboras are somewhat delicate and do not tolerate elevated nitrates or swings in water chemistry. Acclimatise very carefully. This species is rarely seen in the trade, and when it is available, may also be seen on sale as the Polkadot Dwarf Rasbora or Yellow Polkadot Rasbora. Rather confusingly, some of the more colourful Boraras species have been muddled with this species in aquarium literature due to suppliers sometimes listing Boraras brigittae, B. maculatus, and B. naevus as the misnomer Boraras sp. "œred micros".

Feeding

Small frozen foods such as baby brineshrimp, mini-bloodworm, cyclops, and daphnia, plus crushed flake and micropellets.

Breeding

There are currently no reports of the Three Spotted Dwarf Rasbora having been bred in the home aquarium, so this species would make an excellent breeding project for the serious hobbyist. A set up similar to that used for breeding other Boraras species should serve well. B. micros belongs to a group of fish that are known as continual spawners, which is to say that in the case of mature fish, small numbers of eggs are laid daily. In densely planted aquaria with large groups of well-conditioned B. micros, spawnings should occur regularly with eggs being scattered over vegetation and decor. The eggs and resultant tiny larvae will be seen as food by the adults and other tankmates, but if there is plenty of plant cover, some should survive into adulthood. If a greater number of fry is desired, a separate bare-bottomed breeding aquarium (with air powered sponge filter) should be set up with plenty of Java moss/spawning mops and a layer of mesh raised a small way from the tank bottom so that any eggs that fail to adhere to the plants/mops fall through to safety, away from the adults. The water conditions should match that of the main aquarium. Carefully add one or two well-conditioned pair/s of B. micros, and once settled they should spawn the following morning. It is recommended that the adults are moved back to the main aquarium within 48 hours as the first eggs are likely to be starting to hatch by then. The miniscule fry will feed off their yolk sacs to begin with, but will soon require suitably sized foodstuffs such as infusoria and Paramecium, moving on to slightly bigger foods such as Artemia nauplii as they grow. A variety of foods may be needed for a while as you may end up with fry of slightly different sizes from the 2 days of continual spawning. Small partial water changes must be carried out with the utmost of care to avoid shocking the extremely delicate fry.