it's not HLLE
, completely wrong place on the body and looks totally different. HLLE
looks like pits and erosion on the fish. Think of really bad acne scars.
on hippos pretty much always starts around the eyes/face and then progresses along the lateral line, and then slowly progressing outward from the lateral line to the rest of the body.
Does it look like an actual growth on the body like a fungus or does it look like damage and missing scales?
Is it solid and flat against the body or is it textured or fluffy looking, like cotton?
when you say it scratches, does it target that area of it's back or just its gills like most fish do occasionally?
are there any suspicious looking half empty bottles of white-out anywhere near the tank?