yup mantids do fine with corals. They can break your rocks up but usually won't. This guy is really fun to watch. Got him to eat a silverside earlier, tried to get him to punch a chop stick but he just pulled it out of my hand and freaked me out. The light is amazing. Viper HQI 70w. My first MH lighting setup and I'm in love. Definitely going to upgrade the other tanks with MH.