Ok...a Pistol shrimp. They generally keep to the goby's hole and when they do travel, they are always close to the goby. Not likely to hurt fish or corals....although the goby may spread sand on the corals sitting on the sand bed and even bury them. they will protect the "den " den from hermits and snails, but the goby generally does this first.
So long as he doesn't attack my skunk shrimp. Only other small critter is a sixline. Sand bed is bare in some areas and 2"in others. This ok?
I already have a diamond goby so aware of sand dumping