Possibly sick true percula

[volt]

One of my two tank raised true percula clown fish seems a little sick, but does not show any signs that I have read about (this is my first post, but I have been reading these forums for around 3 months). I have had it for approximately 4 weeks, with the first week in the QT tank (I became a little bit impatient with the QT process, but both clowns were active and eating well and I have heard that the tank raised clowns tend to be in a lot better health than the wild caught). The behavior that I am noticing is that the healthier fish moves around the tank quite a bit and explores (and even surfs in the power head flow), while the other tends to stick to a certain part of the tank (lately it has been behind a rock formation). Both fish are quite active while I feed and respond to me even if I am just looking at them. I have noticed what look like small abrasions on the more languid of the fish, but they are small enough to where I would never be able to get a clear picture of them. The only other fish I have in the tank is a lawnmower blenny, which is fairly apathetic to the presence of the clowns. A month seems like a long time for any of the diseases that I am aware of (am under the impression that most kill pretty quickly), could this still just be stress from transport, or an attack from its LFS tank mates? Is there anything that I can do to help it heal? Is this within the normal personality ranges of clown fish? This is my first tank, so I am lacking in experience, but I think I've read every book available for reef tanks (without going and taking some chem and bio courses, heh).

My tank params are:
Temp 80
PH 8.2
Ammonia 0
Nitrite 0
Nitrate 0
Phosphate 0
Calc 400
Tank is 2 months old with around 55lbs of live rock in a 55gal tank with a 10 gal sump and 3.5in sand bed. Various snails and mithrax crabs out and about in the tank

Any ideas are very welcome

Thank you,
Jason