The exclamation point rasbora (Boraras urophthalmoides) is a small fish found in Southern Thailand where it inhabits shallow bodies of water such as swamps, marshes, floodplains and rice paddies containing submerged vegetation in predominantly clear water. This fish grows to an adult size of about just over half an inch long. Mature females are noticeably more round and often a little larger than the slightly more colorful males.
Exclamation point rasboras should be maintained in an aquarium of 10 gallons or larger. A soft, sandy substrate (CS7538) is a good choice. Driftwood (ZM2000) and live or artificial plants may also be incorporated.
Exclamation point rasboras prefer a temperature of 68°F to 82°F, a pH of 6.0 to 7.0, and a hardness of 1 to 20°H. Be sure water is clean and well oxygenated. Filtration should be adequate, but gentle.
The exclamation point rasbora is a very peaceful fish well suited to a planted aquarium. Good tank mates include other small rasbora species, scarlet badis, pygmy cories, and otocinclus. These small fish will do best when kept in a shoal of at least 8 to 10.
In the wild, the exclamation point rasbora is an micro predator. In the aquarium it will readily accept flakes (AL165) and small frozen foods. For maximum color, growth, and health these fish will look their best when given probiotics (AL169) in addition to a balanced diet.