Hey Deb, thanks for the reply. Yeah I plan on doing a good bit more research on these guys. In my tank I have:
1 False Perc
1 Bi-color Blenny (very small)
1 Wheeler's Watchman Goby
1 6-line Wrasse (also very small)
1 Tiger Pistol Shrimp
1 Peppermint Shrimp
1 Cleaner Shrimp
1 Emerald Crab
Snails and Hermits
1 Feather Duster
I don't think anyone is very aggressive in my tank. My pistol just snaps at people when they get too close to his holes, but hasn't hurt anyone.