Chili Rasbora swimming in tank

Chili Rasbora Care: Tank Setup, Diet, And More

The Chili Rasbora is a strikingly beautiful, tiny schooling fish that is popular in nano tanks, community tanks, and planted tanks. They are extremely active and inquisitive fish, making them extremely popular with aquarists. 

They are also colorful with bright ruby red coloration that pops out in contrast in planted aquariums. They get along well with most other fish (as long as the other fish don’t mistake them for a snack) and peaceful invertebrates.

In this guide, we’ll walk you through their optimal care conditions including ideal tank set-ups, tank mates, water conditions, and more.

Recommended Chili Raspora Care Items:

Chili Rasbora Overview

The Chili Rasbora’s scientific name is Boraras brigittae. It is also known as the Mosquito Rasbora. They’re native to Southwestern Borneo, where they live in blackwater streams and pools and can be found in some peat swamps. The name Mosquito Rasbora originates because of their natural habitats, which contain millions and millions of mosquitos. If you’re interested in setting up a blackwater tank, this species is a good stocking candidate.

Technically, Chili Rasbora fish aren’t part of the Rasbora family. Although initially categorized as a Rasbora, scientists re-classified  them as Boraras in 1993. However, the old name has stuck in the aquarium trade. 

These tiny fish are some of the smallest tropical fish found in home aquariums. They’re known for their bright ruby red color, peaceful temperaments, and inquisitive behavior. They’re not super difficult to take care of but do have some strict care requirements for maximum health.

Chili Rasbora Appearance

Chili Rasboras are glamorous fish. Their defining feature is their bright ruby red coloration. The use of the word chili in their name conjures up fiery reds, bright oranges, and saturated pinks and these tiny fish have it all! 

As you might expect, their bodies are covered in shades of red and pink. The red coloration is brightest on the horizontal stripe that runs the length of their bodies. The red stripe runs in tandem with a deep black stripe, bringing full contrast. 

Chili Rasbora close-up

Males also have bright red spots throughout the fins, which are really easy to see because the fins are all translucent. Because of the clear fins, it looks like there are unique spots of color floating around the fish. These spots appear on dorsal, anal, and tail fins. 

Chili Rasboras are slender in their body shape – kind of like a narrow torpedo. They are widest around their midsection, but their body tapers to a point at their head and tail fin. 

How long do Chili Rasboras live?

Under ideal conditions, the average lifespan of this species is somewhere between 4 and 8 years. When we first found this out, we were surprised. While this is shorter than some of the larger fish in the aquarium trade, this is a pretty solid lifespan for a fish this small.

However, lifespan is heavily affected by the quality of care they receive – specifically water conditions and overall stress level. If your fish are constantly stressed, you will be lucky to get four years out of them.

How big do Chili Rasboras get?

The typical Chili Rasbora size is about .75 inches long! This nano fish is tiny by all definitions. Because of its size, it is considered to be an excellent candidate for nano aquariums. 

Chili Rasbora Temperament

Chili Rasboras are peaceful fish that do well in community tank settings. They do best in schools of 6 or more, although much larger schools of 20+ are ideal. They will swim together in unison, creating a beautiful moving school of color in your tank.   In larger groups, they are more comfortable exploring their tanks and you’re less likely to see shy behavior.  They typically swim in the top and middle level of the water column.  

This species is safe with other peaceful, small fish and dwarf shrimp.  Typically, Chili Rasboras will stick to the upper half of the aquarium. They may venture down to the bottom of the tank on occasion, but that’s less common.

Chili Rasbora Care

You need to know what you’re doing with Chili Rasboras. They’re small fish that can’t tolerate extremely wide fluctuations in the same way a larger fish would be able to. Stress gets to them so its important to stay ahead of any major changes so you can keep them happy and healthy.

Mosquito Rasbora in community tank

Our guide covers their ideal habitat, including tank, breeding, filtration, and more.

Chili Rasbora Habitat

When planning the ideal Chili Rasbora tank, it is recommended to try to recreate their natural environment. This principle works well when designing tanks and making sure your fish are eating correctly. Recreate their natural environment for best results. 

The natural habitat of these fish consists of blackwater pools and streams, with slow-moving water. The water is often peat-stained, with pH as low as 4.0.

Their natural environment water is dark and dim, with lots of natural hiding spots behind fallen leaves and vegetation, submerged branches, and twisted tree roots. Additionally, their natural living quarters are further shaded by dense canopy overhanging trees that block the sunlight.

In other words, a super clean, bright, sterile aquarium with neutral water does not reflect their natural environment. 

So now that you know the basics of what these tiny fish like, let’s explore each component of how to recreate their world.

What is the best tank for a Chili Rasbora?

Because of its tiny size, the Chili rasbora is a candidate for a nano tank. This means you can keep this species in tanks as small as 5-gallons.

That being said, we do recommend a larger tank if you have enough space. These fish do best in large groups, with 20+ the ideal size, so you will need a larger tank to house a group this large. Consider looking into a 20-gallon tank if you’re able.

Our Pick
Tetra Aquarium 20 Gallon Fish Tank Kit, Includes LED Lighting and Decor

What We Like About This Tank

  • Provides ample living space
  • Includes a filter and heater
  • Includes decor to provide hiding places
Check Price on Amazon

Additionally, regardless of the school size, a larger area for swimming and exploring is preferred. It helps prevent your fish from feeling cramped, helping to keep their stress levels low,  and gives you more opportunities to create hiding spots for them if they’re feeling shy.

How many Chili Rasbora can go in my tank?

You can keep six Chili Rasboras in a fully cycled, established tank. In a 20-gallon, you can include about 25 fish. This is why we recommend the larger tank size, as these fish thrive in large groups.

Water Conditions

Water conditions for Chili Rasbora are very important. They’re small fish so they can’t tolerate wide swings in their water conditions, which means they need properly managed, stable parameters. This is where most beginning aquarists struggle with this species.

Because of their need for stable conditions, we don’t recommend adding this species immediately after tank cycling. Similar to neon tetras, they’re better choices for established tanks versus introductory fish in new tanks. Understanding the nitrogen cycle is an important element of successful fish keeping.

Chili rasboras are native to blackwater habitats with soft water containing very few minerals or salts. To mimic these conditions, the water hardness should be between 3 and 12 dKH, and the pH range should be from 4.0 to 7.0. Ideal water conditions include:

  • Water temperature: 68°F to 82°F (74°F is best, middle of the range)
  • pH levels: 4.0 to 7.0 (6.0 is best)
  • Water hardness: 3 to 12 dKH

Keeping the pH on the acidic side is important. Learn about lowering the pH if this is a new concept to you. 

Additionally, we recommend testing weekly with this Water kit. Aim to test the water parameters once a week. Testing the water is the only way to stay on top of the invisible changes that occur in the water quality of your tank.

What to put in their tank

Chili Rasbora live in dim waters with lots of natural hiding spots under fallen leaves, submerged tree branches, and tangled plant roots. An environment like this is ideal and should be your goal when thinking about to include and not include in their tanks. 


A dark-colored substrate will keep the tank darker, mimicking the natural environment, and will also make your Chili rasboras intense colors pop with the contrast. These fish are middle to top level swimmers, so fine gravel or sand that mimics a river bottom is a good choice. They’re not going to injure themselves on the substrate.

These fish also prefer planted tanks, which is important to keep in mind when selecting a substrate.  We recommend something like Seachem Flourite Black Clay Gravel or Flourite Dark for your planted tank.

Additionally, if you want to recreate a blackwater look (while also keeping the pH low), we recommend looking into Indian Almond Leaves as a natural way to add tannins to your water.


The natural habitat of the Chili Rasbora includes slow-moving bodies of water. If your filter generates too much water current, your fish will get stressed with their attempts to swim against the current. 

If you don’t already have a filtration system, you can look into canister, HOB filters, and sponge filters (in order from most power to least power).

We recommend either a sponge filter or a HOB filter, because they’re less likely to be too powerful. You can also add plants and driftwood to break up the flow from your filters in order to give your fish easy swimming areas. Lastly, we recommend using a power strip for your aquarium to protect against power surges and keep your aquarium cabinet space organized.

We also recommend purchasing a filter guard for your system as the filters can sometimes suck in Chili Rasboras and accidentally kill them.


Driftwood, rocks, and planted tanks are recommended for Chili Rasboras. The goal is to create a natural environment so the bubbling treasure chest isn’t the best fit here.

Our Pick
Seiryu Stones for Aquascaping and Aquariums

What We Like

  • They add to the aesthetic of your tank
  • They help provide places for your aquatic critters to hide
Check Price on Amazon


Live plants are important for this species. Chili Rasbora love plants like Java Fern, Java Moss, Amazon Swords, and Anubias. Plants help improve water conditions by removing nitrates from the water. Additionally, they provide lot of nooks and crannies for your fish to hide, which helps keep their stress levels low.

Chili Rasbora Potential diseases

Important notice: we are not veterinarians at Aquarium Friend so the information below should be used for general awareness only. If you are concerned about the health of your electric blues, consult a fish health professional immediately.

Chili Rasboras don’t have any species-specific diseases. However, you will still need to keep an eye on common freshwater fish illnesses such as parasitic infections and fungal problems.

The most common issue for freshwater fish is Ich. It is a contagious disease so once it gets going in your tank, you will want to quickly address it to stop the spread. If you act quickly, you should be able to get the infection under control without losing any fish. 

In most cases, Ich is caused by stress. The best cure is prevention, so maintain stable water conditions and provide your fish with a healthy diet. However, if you do get caught with an infection, there are lots of over-the-counter medications that can address Ich.

Chili Rasbora Feeding 

Feeding Chili Rasbora is not complicated. The main challenge is finding food small enough to fit inside their mouths.

Chili Rasboras are considered micro-predators. Fierce and tiny. In the wild, they eat things like plankton, worms, and insects.

What should you feed a Chili Rasbora?

In captivity, feed them a balanced diet of fish flakes or granules. They do best with supplemental protein snacks such as baby brine shrimp, micro worms, and Daphnia. For best coloration and health, feed them a varied diet.

How often should Chili Rasbora eat?

Chili Rasbora are tiny fish so it is easy to overfeed them. We recommend feeding them once a day max, and only feed what they can consume easily in 1-2 minutes.

Chili Rasbora Tank Mates

Chili Rasbora are peaceful fish. However, that doesn’t mean you can put them with all species of fish! Because of their size, a lot of other fish will consider them a good snack. Best to avoid that situation. They also do well with lots of peaceful invertebrates, including dwarf shrimp. Because they’re peaceful, they’re also common starter fish for kids (as long as parents can ensure healthy living conditions). Here are some tank mates to consider:

Are Chili Rasbora fin nippers?

No, Chili Rasbora are not known to be fin nippers. As long as they’re housed in a sufficiently large tank with other Chili Rasboras, they’re likely to be happy and easy-going community tank members. They’re tiny fish so it would be a bad strategy for them to be aggressive fin-nippers as it would cause conflict that they wouldn’t be likely to survive.

Chili Rasbora Breeding

Breeding Chili Rasboras is easy. If conditions are ideal in the tank, these fish are continuous spawners, meaning they will lay eggs regularly.

However, if you want to reap the fruits of your fish’s labor, you will need a separate breeding tank to protect the spawn. Remember that Chili Rasboras are sensitive to water changes, so make sure that the temperature, slow, pH, and hardness is consistent in both your regular and breeding tanks. When you’re trying to breed fish, it is not the time to unnecessarily and accidentally kill them because of sudden parameter shifts.

Chili Rasbora are not protective of their fry and will eat them or look the other way while other fish snack on them. It is recommended to add lots of vegetation or mesh nets at the bottom of the tank to give the fry lots of hiding places. 

When Chili Rasbora are spawning, it looks like they are chasing each other around the tank. Females will scatter eggs throughout the bottom of the tank. When this occurs, it is time to remove the parents from the tank so they don’t eat the eggs and fry.

The eggs hatch quickly – usually within a couple of days. For the first 24 hours, the fry will eat the egg sac. After that, they’ll start to consume microscopic food like Infusoria and paramecium. After 10 days, you can switch to micro worms.

How to Sex Chili Rasbora

Male Chili Rasbora usually have darker black and red highlights on their dorsal and tail fins. When breeding time occurs, their coloration deepens. Female Chili Rasbora are slightly larger, duller, and plumper.

Chili Rasbora FAQs

Will Chili Rasbora eat baby shrimp?

Chili Rasbora are some of the safest fish you can keep with shrimp. It is unlikely they will eat your baby shrimp, and even if they do, they’re so small that they won’t be able to pick off significant numbers.

Do Chili Rasbora need a heater?

Chili Rasbora can live in water temperatures that range from 68°F to 82°F. Middle of the range, or around 74°F, is best. If your water naturally stays around this temperature, then you’re ok without a heater. However, we recommend using a heater with this species because they’re extremely susceptible to water fluctuations. A water heater is peace of mind that your water won’t dip below a certain temperature.

Can Chili Rasboras live with bettas?

Yes, Chili Rasboras can live with bettas. However, they will need to be in a large enough tank to comfortably house a group of 6+ Chili Rasboras (ideally 20+) and your Betta. They eat similar foods so there is good overlap in their diets. You will want to provide plenty of places to hide and try for Chili Rasbora (plants, driftwood, rocks, etc.) and keep the light a little dimmer. This will imitate their natural habitat and make them less stressed.

How much do Chili Rasboras cost?

Chili Rasboras range in price, with discounts usually extended for buying more than one. Single fish can run around $5 for a single fish. Larger groups can cost $3-5 per fish.

Do Chili Rasboras jump?

Chili Rasboras are not known for jumping. However, there are reports of them making a leap for it so it is recommended that you keep a lid on your tank to prevent any daring antics. They’re such small fish that they won’t last long outside of their ideal conditions.


Now that you’ve learned just about all there is to know when it comes to caring for Chili Rasboras, you should be able to decide for yourself if they’re a good fit for your aquarium.

Chili Rasboras are tiny, peaceful community tank members. They’re a favorite of aquarists who love their flashy reed color and active behavior. They can live in harmony with both shrimp and fish tank mates but avoid aggressive fish who will snack on your small fish.

If you can keep stable water conditions, they make beautiful additions to any community tank with their pops of color and relatively long lifespans.

Leave a Comment

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.