Hi, just recently I've noticed a change in my dwarf gourami. He looks more grayish on top than he usually does and I've also noticed what looks like a bruise under his left eye and another on his left side near his belly. Is this a sign that he has been bullied or could it be the start of another disease? I've also noticed that he only stays in one area of the tank....usually he is swimming around the whole of the tank. He won't even come to the glass to greet me as he usually does. Its almost like he doesn't want me to see him up close. He is in a community tank with 2 other pearl gourami, but I rarely see any of the gourami attack one another. I also have a red tail shark in the tank, could he be the culprit....he likes to rule! I have already lost one of my dwarf gourami to something unexplainable....he was fine in the morning...dead that night. Really don't want to lose another. What other symptoms of bullying should I look out for?