Chili Rasboras Care: Diet, Size, Tank Size & Temperature

Scientific NameBoraras Brigittae
Common Name(s)Mosquito Rasboras / Chili Rasboras
OriginSouth Western Borneo
Temperature Range68°F to 82° Fahrenheit
Water ParametersGH: 1-2, KH: 3-12 dKH, pH: 4.0-7.0
Adult sizeabout 0.7 inches
Dietomnivorous, but prefer more carnivorous diet

 Chili Rasboras Facts:

  • They are a nano fish that prefer to live in a school of their own species, but can be added to a tank with a community of other small, peaceful fish.
  • They are a fish native to Indonesia. More specifically, south western Borneo. They inhabit blackwater streams, pools, and can be found in some peat swamps with a pH as low as 4.0.
  • They are a super active fish, and are described as having a delightful character with big personalities. This makes them a popular freshwater aquarium fish that add a pop of stunning ruby color to an aquarium.
  • They are rarely sold in pet stores, but they can easily be purchased online. They are not an expensive fish to purchase.
  • Coupled with their playful behavior, their bright, flashy coloring makes them an eye catcher in any aquarium. The less stress they have in their environment, the more brightly colored they become.
Chili Rasboras

Chili Rasboras Care

Chili Rasboras are a beautifully colored, freshwater, nano schooling fish. They are red-orange in color with a black and red line that runs down their mid lateral line. The males are more brightly colored than the females, but they all share these eye catching color traits. Their flashy coloring and active nature makes them a favorite of aquarium owners all over the world.

The Chili Rasboras are native to southern Borneo, and live in blackwater streams, pools, and peat swamps.

These nano schooling fish are very active, but mild natured. They won’t chase or nip the fins of other fish, but their small size is less than ideal for a tank with other larger species. They don’t do well in an environment with a more aggressive feeding fish. This tends to stress the Chili Rasboras, and dull their coloring.

Food and Diet

Chili Rasboras are omnivorous, and can eat a variety of vegetable and plant matter as well as meaty protein. The biggest challenge in feeding the Chili Rasboras is finding food small enough for them to eat. They have very small mouths, and they can starve if the food given to them isn’t small enough.

Although they are omnivorous, they do prefer a more carnivorous diet. Live foods are a great option for feeding time. Micro worms, mosquito larvae, and small bloodworms are among their favorites. Frozen foods are also an option, but will need to be thawed and chopped into small enough pieces for them to eat. They do best when they are fed twice a day.

Chili Rasboras Size

The Chili Rasboras are among one of the smallest tropical fish kept in aquariums. At full maturity they can grow up to 0.7 inches in length. They are shy, timid fish around other species. They prefer a single species community set up.

Tank Size Requirement

The Chili Rasboras are a schooling fish, and they have a minimum tank requirement of 5 gallons. The minimum requirement for the school is 6 Chili Rasboras, and they can be kept in a minimum of a 5 gallon tank that holds only Chili Rasboras. An additional 2 can be added per gallon after that. Schools of 20 or more are ideal, but not a requirement.

These nano schooling fish thrive in densely planted aquariums with a dark, fine textured sand or gravel substrate. Their natural habitat contains acidic water rich in tannins and leaf litter. Floating plants are a wonderful addition to their tank as well.  

They can cohabitate with other peaceful nano fish, but their size makes it more difficult to find other fish suitable for tank mates. Other small cyprinids such as other rasboras, minnows, tetras, as well as dwarf cichlids are good choices to add to an aquarium with Chili Rasboras. They can also be housed with shrimp, but they will eat the shrimp babies.

Are Chili Rasboras Hardy Fish?

Not unlike other fish of this type, the Chili Rasboras are sensitive to temperature fluctuations in the water, as well as nitrites and ammonias. Ideally, they need a 10 to 15% water change weekly to keep them happy and thriving. Owners of these fish describe them as an intermediate level fish to care for, and not ideal for beginners. It can be difficult to replicate breeding conditions for them.

They are described as hardy fish with lifespans of 6 to 8 years in the right conditions. They are a strong fish, but they are very small and sensitive. They cannot thrive in a dirty tank, and it is recommended that their substrate is cleaned regularly.


Since the Chili Rasboras is a fish native to South western Borneo, they require a warmer water temperature. They are sensitive to temperature changes, and they do require a submersible aquarium heater to maintain a stable water temperature. It is recommended to check their water temperature weekly with water changes to ensure that your heater is working properly. The heater thermostat should be kept at 68°F to 82°Fahrenheit.

Do Chili Rasboras Jump?

They are officially listed as non jumpers, but owners of these fish have reported them jumping out of open top tanks. Since they are small in size, they do run the risk of getting stuck in places that much larger fish would not, such as filters. 

Fish Laboratory

With decades of collective fishkeeping experience, we are happy to share the fish care tips that we've picked up along the way. Our goal at Fish Laboratory is to keep publishing accurate content to help fishkeepers keep their fish and aquarium healthy.

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