I have an african clawed frog, a glass tetra, a ghost shrimp, and 2 angel fish in my tank. I recently noticed that the glass tetra is swimming after and butting the white angel fish to the point where the angel fish has to hide behind a plant. I was wondering if this behavior could be a problem, and if it is how do I remedy it? The tetra doesn't go after the black angel fish which is the same size as the white, or the frog.