yup, they are reef safe and necessary in large numbers to keep some fish....sometimes there the misperception that some of them eat corals, and it is true, but only if it is dead or dying or has dead or dying tissue on it. This can be highly debatable topic especially in concern to Little Red Bugs, which are a amphipod, and can infest your acroporas. Most people eradicate them form their tank using a dog dewormer called Interceptor. When you treat your tank with this it will kill 99% of all your pods along with many other things. There are very experienced reefers on both sides of the board as to whether they truly are harming the corals, or are just irritating them and possibly symptomatic of something else.
I pesonally am on the fence. I have treated my tank for them and gotten rid of them and i do believe that I achieved a little better polyp extension after doing so, but i have also had acro eating flatworms which are infinitely a more serious threat to your corals, and i know of more than several people who became frustrated and finally beat aefw's by simply tossing all of their corals and starting over.