I have 3 New Guinea reds 1 golden gourami 9 golden barbs 2 plecos but he is by far larger than all of the other fish the only fish bigger than him is another roseline
I have a 50 gallon planted tank all the peramiters seem to be good to go (use API liquid test). The issue I am having is out of no where my roseline that I have had for a while formed a spot above his eye that looks like he has been attacked. I am new to the hobby and simply do not know how to...