just a quick question to see what everyones opinion is or experience is, but looking to put 2xyellow coral goby with 2x ocellaris clown fish, in a 15.5 Gallon, live rock ( may like an a nem but need more research- they are tank bred clowns without nems) crushed coral at the moment- going to mix with sand (recommend size?) or should i just put the clowns in alone? are coral gobies safe from peppermint shrimp and hermit crabs?