* Chili rasboras are a small, peaceful fish that are also suitable for a 2-gallon tank.
* Least killifish are another small, hardy fish that can be kept in a 2-gallon tank.
* Neon tetras are a small, schooling fish that are also suitable for a 2-gallon tank.
* White cloud mountain minnows are a small, peaceful fish that can be kept in a 2-gallon tank.
It is important to remember that even small fish need space to swim and hide, so it is important to not overcrowd your tank.