so I took a rock out of a sump because it had this really cool sponge growing on 50% of the rock and placed it in my main display, its just an off white sponge that is 1/2 in thick but growing. after 3 weeks in the tank it seems to want to take over anything around it. I had a hammer that is pretty big next to it and it took over the stalk of the branches growing up to the heads. doesn't seem to be affecting the hammer heads. just looks funny. it seems to be spreading onto other rocks around it as well. its definently a sponge. looks like what I wash my dishes with , could this stuff become an issue?

