Ok, I have this yellow sponge that is overtaking one of my rocks. It's to the point that I can't put anything on the rock, because the sponge just smothers it. Taking the rock out is not an option, since it is on the bottom of my tank and I would utterly destroy several corals to get to it. So, what eats sponge? I have got to take some kind of action before this blob takes over the right side of my tank completely. Anything out there that would be reef safe but still eat sponges? BTW, I have no "display" sponges, so said critter could eat to its' hearts content.