Is My Shark Sick?

[bosemimi]

hi
i have noticed today that my white albino shark's mouth is looking reddish and swollen,it is hiding behind the wood,and eating only when i am giving food,generally it is very active and searches for food.dont know whats happening to it?tank condition is perfect and all other fishes are doing good.
thanks
anindita

 

[WILDER]

Water stats would be good in ammonia,nitrite,nitrate,and ph.
Has he injured his mouth on something.
Can you issolate him as if its really red and swollen I would use a bacterial med on him.