Although most would presume that Bettas fare best when surrounded by the same species, this notion could not be further from the truth. Bettas are fighters and males are quite territorial.
So what about a male and female in the same tank? Unfortunately, they too can get into scuffles that could hurt the other fish in your aquarium. Therefore, Bettas are content with the most peaceful species of fish. Additionally, when choosing other fish to inhabit the tank with your Betta, ensure they enjoy or can adapt to the same water temperature.
Please note: Bettas have varying personalities. You will find much conflicting information out there because Bettas can react differently depending on their surroundings. As a general rule, males do NOT go well together with males, and since Gourami fish resemble Bettas, exercise caution with this species.
Glass Catfish – This is an interesting fish because it derives its name from having a transparent appearance. A very docile fish, the Glass Catfish does best with other fish, which also includes the Betta.
Coolie Loach – This is an excellent fish to “room” with your Betta. They are peaceful and spend much of their day resting on the aquarium floor amongst the vegetation. Since it’s important that Bettas do not overeat, the Coolie Loach can help keep the Betta healthy by acting as a scavenger, eating all the leftover food in the tank.
Rasboras – Naturally found in the Southeast Asian waters, this species is one of the best types of fish for a home or business aquarium. As small fish with lengths at or less than two inches long, they eat all types of fish food and the environment they love is similar to the environment in which the Betta thrives as well.
Note: Exercise caution with Gouramis. I have seen them make great tank mates and I have also seen them get quite aggressive with bettas since they closely resemble bettas.
Blue Gourami – Very closely related to the Betta, this species also requires the exact same aquarium care as the Betta, which makes it the perfect tankmate. Obviously, they are beautiful shades of blue hues.
Croaking Gourami – These fish are very adaptable to the Betta environment and they add beauty as well as colors of blue and red up and down their bodies, from head to fins.
Dwarf Gourami – Having the same beautiful coloring as their cousins above, along with some peacefulness, this little fish barely reaches a length of two inches and is also a perfect species to be “room” with your Betta.
Pearl Gourami – These are the largest variety of the Gourami Fish because they easily reach a length of four inches or slightly more, and this species looks as if an impressionist painter added his technique to the fish’s body. They are a great fish to add to a tank with your Betta, but because of its size, the tank where it resides should be at least 30 gallons.