Ghost Shrimp Killing My Guppies?

I've lost 3 guppies over the last three weeks in my planted 5 gallon. The water is perfect and I havent lost any of my neons in the 3-4 months I've had the tank operating. I'm suspecting that the guppy "sleep" closer to the top where I have lots of floating anacharis and the ghost shrimp are on the larger size now. They have been kind enough to clean up the dead carcass in no time at all so I guess that's an upside.

Has anyone experienced this, do you think its possible or am I just getting some bad guppies to start with?