The short answer
Sometimes — it’s hit or miss. A betta is a small predator, and shrimp are exactly the sort of moving snack it’s wired to hunt. Some bettas completely ignore adult shrimp; others pick them off one by one. Baby shrimp are almost always eaten. Whether a colony survives comes down to your particular betta’s temperament and how much cover you give the shrimp.
Why it’s unpredictable
Every betta has its own personality. A lazy, older betta may never chase a fast adult cherry shrimp, while a young, active one treats the colony as a buffet. You can’t tell in advance. What you can control is the odds: a big, established shrimp colony breeds faster than a single betta can eat it, so even with some losses the population holds.
How to set it up for success
- Use cherry (Neocaridina) shrimp — cheap, hardy and prolific, so losses don’t wipe out the colony.
- Add the shrimp to an established, heavily planted tank first and let them breed before the betta goes in.
- Pack in moss, leaf litter and dense plants so shrimp always have an escape route.
- Feed the betta well so it’s not hunting out of hunger.
- Start with 10–15+ shrimp, not two or three.
The safer route
If you want a guaranteed thriving shrimp colony, give them a dedicated tank — see our best shrimp tank guide and how to set up a shrimp tank. For the betta, a nerite snail is a zero-risk cleanup companion. Read more on cherry shrimp and the betta fish, and see the related question can nerite snails live with shrimp?