If you want to add a tiny fish with gorgeous coloration and tons of personality, then the Chili Rasbora is the fish for you.
They are easily distinguished from their larger cousin Rasbora Trilineata by their red body and lateral stripe, giving them an almost chili-like appearance.
Their best habitat is planted aquariums with minimal flow that provide shelter when they need it.
But there’s so much more!
From temperature to pollutants, here’s a guide to give you all the knowledge and confidence you need to create the perfect environment for them.
Appearance
Chili Rasboras are tiny slender fish with large eyes and a cylindrical body.
They are readily distinguished by their red body color and a lateral stripe that extends from the head to the tail.
Small dark spots can be found at the base of the anal and tail fins.
Males have vivid red strips on dorsal and anal fins whereas the females have none.
Females tend to be rounder and duller in color.
Much like its larger cousin, Boraras Trilineatus, Chili Rasbora undergoes a color change as it matures into an adult.
These differences are evident in the redness of its body and the extent of its lateral stripe.
Chili Rasbora Size
I am not kidding when I say that these fish are tiny because they are.
They barely reach 0.7 inches (2cm) long when fully mature which makes them one of the smallest freshwater aquarium fish in the hobby.
This is why they are a favorite for nano tanks.
Overview
The Chili Rasbora (Boraras brigittae) is also known as the Mosquito Rasbora.
This tiny schooling freshwater fish has vibrant color making it a very popular choice for nano, small, and larger aquariums.
They were originally found in streams and ponds throughout Southeast Borneo where mosquitoes thrived. (Hence their name)
Chili Rasboras are not true Rasbora and were moved to the Boraras genus in 1993.
They are easy fish to take care of as long as you are strict when it comes to water quality and tank maintenance.
If the strict water conditions are met then they can live for anything between 4 to 8 years.
Temperament
Being timid in nature they are more suited to a calm environment and are often the only fish species in the tank.
Chili Rasbora is very peaceful and will never nip the fins of other fish.
If they are in a species-only tank then they will be confident enough to explore the whole tank.
You will need to be very careful if they are in a community tank to make sure they are not stressed.
Chili Rasbora fish might take time to adjust to environmental changes but they are adaptive enough as long as the change is done slowly.
Abrupt changes in the water parameters will not be well tolerated and could cause them to fall victim to illnesses like White Spot Disease.
Also, note that they can take up to a month to settle into a new tank and could temporarily lose their color.
Chili Rasbora Care Guide
As I mentioned earlier, taking care of the Chili Rasbora is not difficult.
It is the maintenance of water and temperature stability that is vital to your success.
If you are keeping a school of these fish then make your water changes more frequent and change less of the water at a time.
It is also important that there is not a strong current as they are not used to swimming against the water flow.
Tank Requirements
Chili Rasbora does not like to swim over long distances so they prefer smaller tanks.
I would suggest a school of at least 10 to 12 individuals which will be perfect for a 5-gallon tank.
If your tank is larger than 5 gallons then the rule is two Chili Rasbora per one US gallon of aquarium water.
So, a 10-gallon tank can easily house 20 Chili Rasbora.
If it is a species-only tank then a sponge filter will be sufficient as these tiny fish create very little bioload.
Chili Rasboras live in soft, acidic water with tropical temperatures.
They prefer dim lighting and slow flow.
It is very important to keep the nitrites, nitrates, and ammonia as low as possible as these fish are extremely sensitive and will not tolerate anything but pristine water conditions.
These are the best water parameters to keep your Chili Rasbora fish happy.
- PH Level – 5.0 to 6.0 is best but they can tolerate between 4.0 to 7.5
- Temperature – Between 75 and 80 ºF
- Hardness of the water – 1 to 6dGH but they can adapt to harder water
Tank Setup
Water Conditions
Chili Rasbora thrives in extremely soft and acidic water.
You can make use of a RO Filter if your tank water is not naturally soft and acidic.
Mix the RO water with the normal tap water to adjust the levels.
I have done this very successfully when I wanted to breed Apistogramma.
The other way is to include driftwood, peat moss, or Indian Almond Leaves in the tank.
These elements will make the water more acidic by releasing tannins into the water.
Be aware that the water might turn a brown color.
This is quite normal and it will then closely resemble the natural habitat of the Chili Rasbora.
Flow Rate
The natural habitat of the Chili Rasbora is either still or gently flowing water.
For this reason, it is best to keep the current in their tank as low as possible.
This is why I suggest using a sponge filter for smaller tanks and a canister filter for larger tanks.
Internal filters will be too strong.
Just make sure that any filter intake pipes are covered with either sponge or mesh to avoid the Chili Rasboras from being sucked up into the filter.
Plants
Chili Rasboras love a heavily planted tank with some free swimming space.
Floating plants are also recommended to limit the amount of light coming into the tank.
Lastly, a dark substrate will display their colors better and make them feel more at home.
What to Feed Your Chili Rasbora
These fish are not finicky when it comes to food and will readily accept live food and micro pellets.
They do however tend to be more on the carnivorous side so they will love foods like daphnia, microworms, baby brine shrimp, and mosquito larvae.
Brine shrimp are easy to hatch and grindal worms are also easy to cultivate.
You can feed frozen food but it needs to be defrosted first before adding it to the tank.
Flake food should be crushed into a powder and any other food needs to be finely chopped so that it can fit into their mouths.
Feed very small amounts once a day, just enough for them to eat while swimming as they will not eat food that has sunken to the floor of the tank.
Chili Rasbora Tank Mates
Chili Rasbora is better off as the only fish species in the tank.
However, if you really want to house other fish with them then you need to choose wisely.
The best tank mates for these fish have to have the same peaceful and timid nature that the Chili Rasbora has.
There are a number of fish and invertebrates that I can suggest.
These include the following:
- Threadfin Rainbowfish
- Forktail Blue-eyed Rainbowfish
- Neon Green Rasbora
- Scarlet Badis
- Honey Gourami
- Sparkling Gourami
- Freshwater Pom Pom Crabs
- Red Cherry Shrimp
- Licorice Gourami
- Crystal Shrimp
- Axelrod Rasbora
- Pygmy Corydoras
Chili Rasbora Breeding
Male Chili Rasboras turn a brighter red and the black and red markings on their fins become darker when they are ready to breed.
Females will become rounder and plumper because of the eggs that they will be carrying.
It is best to put a few breeding pairs in a smaller tank if you want to keep the fry.
Chili Rasboras do not normally eat their eggs but if you do come across them then they will devour them.
Set up the breeding tank with the same temperature, flow, pH, and hardness as the main tank.
Then you can go either of two ways –
1) Place marbles or java moss on the bottom of the tank so that the eggs and fry are not at risk of being eaten. The adults are then free-swimming in the tank.
OR
2) Suspend a piece of mesh into the water of the tank and keep the breeding fish above the mesh. The mesh should be big enough for the eggs to fall through but small enough to stop the adult fish from swimming down into the tank.
The female Chili Rasbora will only produce one to two eggs a day.
The breeding fish can be kept for about a week in the breeding tank and then they need to be removed and placed back in the main tank.
As you can imagine, the fry will be super tiny so they will only be able to eat infusoria for the first week.
After that, they should be able to accept freshly hatched baby brine shrimp and microworms.
Conclusion
Even though this is a relatively easy fish to care for, I would not recommend them for beginners.
This is purely because of the pristine water conditions that these fish require.
This is a stunning fish for the more experienced fish keeper who is willing to provide the perfect conditions that they need.
