HITH and HLLE still has quite a bit of research bing done on them.
it is a common problem in cichlid tanks ..more specifically SA/CA cichlids.
there seems to be more info now and more collected.
in the case of HITH there seems to almost always show a flagellated protozoan associated with the cases..the err on this is mis identification of HLLE and HITH.
many times they have been thought to be the same..but in HLLE the protozoan is usually not found.
the thought is these are actually 2 different afflictions with similar end results.
it is known that clean water will help as well as diet.pretty simple if you think about it.. clean water and good nutrion on it's own will help a fishes ability to reconver from an infection as well as help it maintain a healthy immune system.
atm there is study being done documenting the shape of the damage done..HLLE may have a lateral shaped wound HITH more circular (round and pinhole)
but the jury is still out on this.
the discoloration on him is too faint to really see markings/pits/pockmarks...whatever you want to call them. In my case, I really think it is the nutritional issue as all the other potential sources have been eliminated. Except for the Protozoan infection...but I would probably have to super stress my fish by catching it, holding it, swabbing the area, and bringing the sample to my lab to test for that possibility.
Not worth it when he probably needs more vitamin C, I'd say.