2nd Cleaner shrimp that has been eaten ... ???

[RMA110731]

My last cleaner shrimp lasted 2 1/2 months then someone in my tank ate him

I just purchased another one about 3 weeks ago -- someone in the tank would eat the antennae off the shrimp ( even my fire shrimp, but he is still ok)

Well the one I bought 3 weeks ago is gone today -- only remnants of him left in the tank -- with all fish picking now --

Is this common? Should I not even think of getting another one??

Any suggestions are welcome