This is in a 3-gallon tank with Cherry and Bee Shrimp, Nerites and MTS. No fish. I have had bad luck with fish in the tank because it has no top and they tend to jump out easily... I would throw my wife's beta in there, if I thought it would leave the shrimp alone...
Those pictures were taken a few weeks ago... Here is a more full shot of the tank, to give you an idea. It is pretty heavily planted now.
They don't seem to bother anything, more of an eye soar. Is there a good small fish I could add to a tank this size that would eat these things, while leaving the shrimp alone?