Rainbow sharks cannot live together in a tank. In the wild, rainbow sharks lead solitary lives. Moreover, they’re very territorial and cannot tolerate others of their own kind.
As a general rule, you should only keep one rainbow shark in a tank, especially if you’re a novice fishkeeper.
With that said, if you insist on keeping more than one rainbow shark in a tank, there are some guidelines you can follow:
- Never keep just a couple of rainbow sharks
- Keep at least five rainbow sharks together, so the dominant ones have multiple rivals to chase around
- Introduce them when they’re juveniles
- Each rainbow shark needs at least a meter of separated territory