Exclamation point rasbora care

Boraras urophthalmoides · Mainland Southeast Asia

Exclamation point rasbora (Boraras urophthalmoides)
Photo: R.workoran, CC BY-SA 4.0, via Wikimedia Commons

Exclamation point rasboras are tiny amber fish, about half an inch long, with a dark stripe that ends in a dot.

Tank size
5 US gal or larger
Temperature
72 to 82 °F (22 to 28 °C)
Group size
8 or more
Temperament
Peaceful
Adult size
0.6 in
pH
5.5 to 7
Hardness (GH)
1 to 8 dGH
Lifespan
3 to 5 years
Diet
Micropredator
Care level
Moderate
Check it in the stocking checker →

In a 5 gallon: Aqueon 5½

16 3/16 × 8⅜ × 10½ in outside
Drawn to scale: 8 exclamation point rasboras at adult size (0.6 in) in the smallest listed tank that suits them. Choose your tank on the home page to see them in it.

How to keep exclamation point rasboras

Exclamation point rasboras are tiny amber fish, about half an inch long, with a dark stripe that ends in a dot. Keep eight or more in a 5 gallon or larger planted tank at 72 to 82 °F with soft water and only other very small, peaceful fish or shrimp.

Diet: Micropredator: crushed flakes, baby brine shrimp, micro foods. Fish food types compared · how often to feed.

Where they swim: Middle of the tank.

Exclamation point rasbora tank mates

Share the temperature and water, and neither side eats, nips or bullies the other. Check the full group in the stocking checker.

Keep apart

What an exclamation point rasbora tank needs

A tank of 5 US gallons or more (such as the 5 gallon: Aqueon 5½) with a cover, and the equipment below.

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Aquarium Co-Op Easy Flow Sponge Filter, Nano

A sponge filter gives gentle flow and cannot pull in small fish. It runs from an air pump, with airline tubing and a check valve, all sold separately.

Aqueon QuietFlow Internal Power Filter up to 5 gal

Rated by the maker for up to 5 US gal, which covers a 5 gallon exclamation point rasbora tank without being built for a far bigger one.

hygger Hang-on-back Canister Filter 5W

Rated by the maker for up to 10 US gal, which covers a 5 gallon exclamation point rasbora tank without being built for a far bigger one. Its surface skimmer can pull in small fish: cover it with sponge or mesh, as hygger advises.

hygger Precise Aquarium Heater 50W

Exclamation point rasboras need 72 to 82 °F; most homes run cooler, so a heater holds the temperature.

API Freshwater Master Test Kit

Tests ammonia, nitrite, nitrate and pH, the readings that matter most before and after adding exclamation point rasboras.

Seachem Prime 100 mL

Removes chlorine and chloramine from tap water at every water change.

Fluval Edge Thermometer

Shows the water temperature at a glance, so you know it stays within 72 to 82 °F.

More choices, each with the reason it is in or out: Filters for a 5 gallon tank · Heaters for a 5 gallon tank. We don’t list fish food: any good brand of the foods under Diet will do. Plan the whole tank's equipment →

Common exclamation point rasbora problems

Test the water first whenever fish look unwell: see what your readings mean, then match the symptom. For disease, a vet who treats fish can diagnose it and advise treatment.

More to compare

Sources

Name, origin and adult size checked against Wikipedia: Boraras urophthalmoides. Temperature, pH, hardness, group size, lifespan and minimum tank size are common hobby guidance, not figures from that article. Ranges are the range the species tolerates; aim for the middle. Minimum tank sizes are for an adult group. Drawings are our own; photo credits follow.

Photo credits

Real photographs from Wikimedia Commons, resized and cropped to fit; each is used under the license named.