Mantis to 12G nano

[sacase]

ok I had my mantis in a 5 gallon tank alone but I have decided to make my 12 gallon tank Reef only so I dropped him in there. I shouldn't have to worrk about any corals should I? What about a star fish?

 

[ReefGeekster]

Corals can be knocked around though not eaten, the star fish is a 50/50 depends how hungry or bored your mantis is... have a pic?