Never see any aggressiveness to him in perticular he's the boss of the tank the Lima gets scared of him and swims away but the Lima usually is a little aggressive to one of sen
Its not the plec to make an open wound like that he would basically have to be sitting there letting the plec suck on him. Could possibly be heater butn but if ur were it would more then likely be in a line shape. Best bet is disease or possibly fungus.
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