No, you can’t keep a rainbow shark with a betta. Even though bettas are top-dwellers and rainbow sharks are bottom-dwellers, both species are known to be highly territorial and aggressive.
When the two fish eventually see each other, especially if the betta goes to the bottom of the tank, they will certainly fight and injure each other.
Rather than a betta, consider these fish and aquatic creatures to live with your rainbow sharks instead:
- Zebra danios
- Dwarf neon rainbowfish
- Congo tetras
- Neon tetras
- Rummy nose tetras
- Honey gourami
- Rasboras
- Angelfish
- Boseman’s rainbowfish
- Caridina shrimps
- Ghost shrimps
- Nerite snails
- Mystery snails