the ph is 5.2 nitrates and nitrites are at 0 ppm
I dont think this is correct. I can do 80% water changes and still not have 0 nitrates...and I dont have near the fish in a 120 or 55 that you do in your 90.
the ph is 5.2 nitrates and nitrites are at 0 ppm









Still not going to be able to agree on your water Params. But from the new pics it looks like you got someone beating him up.
Mike