I have an aggressive tank. 30" snowflake, 6" koran angel, 3-4" niger trigger, 3" foxface, and 4 damsels. I have some hermit crabs, live sand and rock, and a few snails. Can a gobby live in my tank without being lunch? I know that shrimp are not an option. I don't want to add something to just become a meal. BTW it is a 93 gallon cube tank. It was used for corals before but none now. Thanks!