I've been reading posts on this site for a couple years for advice and finally decided to make my own profile to get help with this problem. I have a golden heart trigger, yellow eye Kole, sailfin tang, and harlequin tusk in the tank shown in my sig. This tank has been up and running for about a year my water tests= pH 8.0, ammonia 0, nitrite 0, nitrates 5ppm, salinity 1.019, and temp is running 75. I intoduced some of the fish without a quarantine tank and had a problem with ich so I started running cuprimine in the display for about two months but I am now in the process of removing the copper. My fish have been flashing some worse than others but it has become terrible now, and acting lethargic at times. The fish appear healthy no spots at all or discoloration and I can't figure out what is bothering them; the trigger went off feed last night. I do weekly water changes 5 gallons at a time with RO water. Any help would be greatly appreciated.