<a href=showthread.php?s=&postid=9474340#post9474340 target=_blank>Originally posted</a> by ScubaTC
My fish are fat and happy (were happy)! The tang that first showed signs of ich is more than 7yrs old. He's the largest and fattest of the four tangs. I've had him for 7 years and got him from someone who had him for at least one year. He may have a lower immune system due to old age???
The problem was first noticed several days after I started feeding nori on a clip everyday, sometimes twice a day. The tangs were bumping into each other when ripping the algae from the clip. I was told that tang's skin/protection is much thinner than most other reef fish so by them bumping into each other at the nori clip may be what started the problem and why it's now spread to all four tangs.