Red Shoulder Serverum

[link101]

Hello, I believe my serverum is ill. Today I notice that he's was shaking his head the breathing seems ok however the only way I can discrbe it is it loooks like he is spitting he is very nervous and his coloring has done very light has not ate in a couple of day's
also in my tank is 2 keyholes, 3 leopard, striped Raphael catfish and rubber lip pleco fish tank is 50G they seem to be in good health. A little history on my serverum as follows about 3-4 inches he was being bullied the problem has be rectified a couple of days ago

I'm concerned has anyone heard of the symptons discribe please help I have been looking and can not find any info

[link101]

Well I treated my tank for parasites thinking it was gill fluke to my dismay it was not. The water that I add in my tank has a ph of 7, however when I checked my ph it was 7.8-8. Did a water change check the ph it was 7. Now a couple of days later the ph is up to 7.2 my tank has been up and running for 5 months. I'm not to sure why the ph went up, I will do another water change to bring in down again anyone have any ideas.
Where I live the fish type I have are not readly avaiable.