Both my frogspawn and leather are growing. It seems as if my frogspawn knows the leather is there. It is putting out sweeper tentacles on the side closest the frogspawn . On occasion thay have extended out far enough to sting the leather. How does it know its there? It has never put out sweepers before this week. Does it sense the reduced light due to the proximity of the leather? Perhaps it could just smell it. I've heard of the chemical warfare between corals. So far it has been simply cold war in my tank.