When setting up a community aquarium, betta fish are a popular centerpiece fish, while rasboras make excellent secondary species.
But can these two fish coexist peacefully?
Generally, yes – rasboras and bettas can make good tank mates when a few simple guidelines are followed.
Compatibility Considerations
Peaceful Temperaments
Bettas are known for being territorial, especially male bettas, so any fish housed with them should be non-aggressive and able to handle the occasional chase or nip.
Fortunately, most rasboras fit the bill with their peaceful temperaments and ability to withstand some mild bullying.
Species like harlequin rasboras, lambchop rasboras, chili rasboras, and galaxy rasboras are particularly recommended.
Their smaller sizes and bright colors also make them attractive contrasting additions next to the showy betta.
Appropriate Rasbora Species
Most types of rasboras prefer to live in schools, so they will need to be added in larger groups of 6-10 individuals.
This prevents them from being singled out and picked on by the betta.
It also allows them to exhibit their natural schooling behavior, which is fascinating to observe in the aquarium.
Meanwhile, only one male betta can reside in each tank unless a female sorority is established.
Habitat Design & Tank Recommendations
Open Swimming Space
Provide plenty of open swimming space along with some dense thickets of plants.
Floating plants are beneficial as well. This allows for natural territories and creates sight barriers.
Rasboras prefer the upper tank levels, while bettas cruise the middle and lower depths.
Set up visual blocks this way so neither species feels cornered or intruded upon.
Tank Size Guidelines
Tank size plays a role, too. For a single betta, 10 gallons works, but I recommend 15-20 gallons instead.
Add at least a few gallons more for the rasbora school – a 15-20 long or 20 high aquarium holds these species nicely.
A long tank has a longer horizontal footprint, while a high/tall tank has more height from bottom to top.
For example, common sizes are:
- 20 gallon long tank: 30” x 12” x 12”
- 20 gallon high tank: 24” x 12” x 16”
Avoid cramped quarters in order to curb aggression. Also, ensure proper filtration to handle the increased bio-load.
Water Conditions & Temperature
In terms of tank conditions, bettas and rasboras have similar requirements where finding common ground is not difficult.
Slightly acidic, soft water with temperatures from 75°-82°F suites both types of fish.
Some species of rasbora also originate from Southeast Asia. If housed together, aim for pH around 7.0, 2-12 dGH hardness, and 78°F for optimal comfort.
Feeding Rasboras and Bettas

When it comes to feeding time, provide a high-quality pellet, flake, or freeze-dried formulation as the staple diet.
Most rasboras are omnivorous and can eat the same foods as bettas.
Supplement with occasional live, frozen, and freeze-dried foods like bloodworms, brine shrimp, and daphnia to provide variety.
In Conclusion
By choosing appropriate rasbora species and meeting the care needs of both fish, bettas and rasboras can cohabitate without much trouble.
Take some time to monitor for aggressive tendencies, and be prepared to separate any problem fish.
But generally, these species can make pleasing tank mates.
The added activity, schooling behavior, bright colors, and contrasting body shapes of rasboras provide added interest alongside bettas in your aquarium.
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