two days ago i noticed one of my juvie intermedia has a wound on the exact spot on both sides of his tail and hes constantly trying to scratch it to the extent that hes doing backflips and cartwheels all over the tank. so far ive added extra aquarium salt and did a small waterchange, the wounds are healing up pretty quickly but hes still scratching himself nonstop. what do you guys think it is? could he have parasite?