Hi, yes they do hear. They receive vibrations along the lateral line the same way that we receive vibrations through the eardrum and the little bones in our inner ear. I read this information on here a while ago, but I did know that fish could hear anyway.My fish actually know my voice. If anyone else stands by the tank and speaks they take not much notice. If I speak they get excited, because they know food is coming. They are very greedy.