it all depends on the size of your tank!
I just bought a 3 gallon tank last Saturday.... along with a heater and 3 shrimp. Oh, and a silk plant. The shrimp are Ghost Shrimp and they go wonderfully in the tank. 1. They're adorable 2. They clean up the surface of the gravel 3. They provide entertainment for Omelette. He bit down his tail to a nub and it's growing back... no more boredom! He's very laid-back so if your betta is aggressive, I don't recommend keeping him with shrimp. He will eat them xD Omelette still takes a peck at them once in a while, but they pinch him with their bitty claws so he keeps his distance most of the time.what kind of shrimp would you recommend?