Care
Thought to be close to extinction in the wild for some time, small numbers were encountered amongst shoals of other rasbora species before additional populations were discovered in areas that had escaped the environmental damage that destroyed their original location. The natural habitats of this species are marshes, ponds, pools and swamps that are quite still and inundated with abundant vegetation.
This type of habitat should be replicated in the home aquarium if you wish to see these fish at their best. The tank can be aquascaped with a dark substrate and background, with plenty of dense planting amid tangles of bogwood. Floating plants can help diffuse bright lighting. Water circulation and filtration should be gentle but efficient. Wild footage shows this fish mingling with Red-tailed (R. borapetensis) and Cherry spot (R. rubrodorsalis) rasboras - something that can be emulated in an aquarium, although somphongsi will happily mix with other small, peaceful shoaling species. Large, active fish will make them nervous, so choose tankmates with care.
The smallest of the harlequin group, settled fish will show a similar warm tone and are unlikely to be mistaken for any of their larger relatives. May be seen as Somphong's rasbora, Siamese dwarf rasbora or Ornate dwarf rasbora. Thanks to a restricted black pattern it hasn't attracted the same lamb chop/pork chop common name as its congeners but perhaps 'Bacon rasher rasbora' might be next?
Feeding
Flake, micropellets, small frozen foods such as daphnia, baby brineshrimp, cyclops and mosquito larvae.
Breeding
Reports indicate that this species spawns on the underside of leaves, like the other members of the genus. Given the conservation status of this fish, breeding is to be encouraged. If wishing to raise a larger number of fry, a separate shallow breeding tank should be set up with soft acidic water (pH 5.5, dH:<5 degrees), a sponge filter, a substrate of marbles and a good amount of broad-leaved plants. The underside of the leaves will be used by the fish for the process of egg laying and fertilisation, and this often begins when the first rays of morning sunshine hit the aquarium glass. The parents should be removed as soon as spawning has ceased, although the male will defend a spawning territory which provides some protection for the eggs. The eggs are light-sensitive, so it is important that the sides of the tank are covered in order to keep the tank in darkness. After 24 hours, the eggs will hatch, and after a further 6 or 7 days, the wrigglers will become free-swimming. The tiny fry will require very small foods, starting with infusoria, and gradually moving on to bigger foodstuffs as they grow. Small frequent partial water changes should be carried out to maximise growth and ensure good hygiene.
