How does that happen? HITH? Is that a parasite of some sort?
HITH and LLE are hole in the head and lateral line erosion. It is two ways of describing the same disease. It affects mostly large cichlids. Oscars seem to be particularly sensitive to it. It is a disease that attacks the sensory pits on their heads and the lateral line on the side of the fish. Both are sensory organs, and the disease erodes them away. It is almost always linked to poor water conditions and/or poor diet.