- Family: Cyprinids
- Scientific name: Boraras brigittae
- Common name: Mosquito Rasbora, Chili rasbora
- Origin: Asia; southwestern Borneo, Indonesia
- Max length: 0.8 – 1.0 inch
- Minimum tank size: 10 gallons
- Stocking: 8-10 fish for a 10-gallon tank
- Temperament: very peaceful, shy
- Feeding: omnivore; accept live, frozen, and flake foods but require regular live foods
- Breeding: very hard
- Habitat: blackwater streams and ponds, Borneo
- Tank setup: densely-planted tank with driftwood and subdued lighting
- Hangs out: top 1/3 of the tank (but will swim lower on occasion)
- Care level: moderate
- Temperature: 68.0 – 82.4°F (20 – 28°C)
- pH: 4.0 – 7.0
- Water hardness: GH 1 – 10, KH 5-10
- Lifespan: 4 – 8 years
- Appearances, temperament, and interesting facts
- Tank setup, layout, and stocking
- Tankmates for chili rasbora
- Diet, foods, and feeding
Appearances, temperament, and interesting facts
Chili rasboras are one of our favorite fish for the nano tank! While they might get lost in a larger setup, they’re perfect for desktop and smaller aquariums.
Some other common names for the chili rasbora are mosquito rasbora and micro rasbora. Males are slimmer, smaller, and brighter than females.
Chili rasboras exhibit typical schooling behavior. They’re really not interested in what you are doing.
In our area, micro rasboras seem to be available seasonally, so it’s taken almost a year before we could order them again. Not sure why, but when ordering chili rasbora, we get so many other species instead. If you want to be sure of what you’re getting, you may want to buy this fish from a breeder.
We placed an order several months ago, then held our breath, crossed our fingers, and hoped that they’d be chili rasboras and they were. Loved them so much, we ordered a second group, which turned out to be Phoenix rasbora.
Phoenix rasboras (Boraras merah)
Phoenix rasboras were supposed to be chili rasboras but turned out to be Boraras merah, instead.
Exclamation point / least rasboras (Boraras urophthalmoides)
Not giving up, and hoping that the third time would be the charm, we placed yet another order and received Boraras urophthalmoides (exclamation point rasbora).
Tank setup, layout, and stocking
Most blackwater fish enjoy a dimly lit tank, and the chili rasbora is no exception. Plants, (both floating and rooted), and a dark substrate will really bring out their color. If you prefer not to have floating plants, then driftwood roots can be used instead. They just like something over their head besides water.
If you really want to make them happy, then scatter some Indian almond/catappa leaves around the bottom of their tank. The leaves serve multiple purposes by adding tannins to, and conditioning the water which makes the fish feel more at home. They also help lower pH, and as if that weren’t enough, catappa leaves have proven beneficial in reducing fungal and bacterial elements.
If you can’t find catappa leaves, then oak leaves will work as well. Whatever you use, make sure they’re dry (not green and still hanging on the tree) and pesticide-free.
Using leaves in blackwater tanks is much more environmentally friendly than using peat. These fish need a clean aquarium, with stable water conditions and do not belong in an uncycled, or newly cycled tank.
Tankmates for chili rasbora
Celestial pearl danios
The chili rasbora can be quite timid in certain situations. However, if they’re happy with their surroundings, then they are far more gregarious and outgoing.
This is a tiny fish and care should be taken when choosing tankmates. Large, boisterous, and/or aggressive fish are out of the question. A species tank, with a minimum of 8-10 rasboras works best.
You know the old adage – safety in numbers, well, the chili rasbora takes this to heart. They become extremely withdrawn and retiring if there are too few fish in the school. Keeping them in sufficient numbers, not only allows them to overcome their natural shyness, it allows you to observe more of their behavior. When sparring, the males become an eye-popping, red.
In a community type of setup, peaceful tankmates such as kubotai rasbora, celestial pearl danios, sundadanios, otos, pygmy cories, and espei rasboras, make suitable tankmates.
One of the best things you can house with these rasboras is dwarf shrimp (they’re super together)! We have ours with a bunch of Orange Sakura, and even at birth, the shrimplets are almost too big for this tiny fish to eat. The rasboras seem indifferent to the presence of the babies.
Diet, foods, and feeding
These are not picky fish and they will accept both flake and pellet food. That being said, they should be fed as much live and frozen food as possible. This makes for a healthier, more colorful, fish.
Some of the live foods they enjoy are baby brine shrimp, vinegar eels, microworms, mosquito larva, daphnia, and chopped-up blackworms. Their frozen favorites include rotifers, cyclops, tubifex worms, and baby brine shrimp.
When choosing a pellet, make sure it’s a micro pellet. Food marketed for small fish such as New Life Spectrum is usually too large for them to swallow.