Raised nems for 7 years and when conditions are right they are care free. Mature stable tank with pristine water conditions and good lighting. My 4 sit 6 inches or less under 2x250 MH
to give you an idea on how intense lighting they need . DO NOT TRY THIS AT HOME, but I only test maybe every 2 months, not bragging or recommending others follow that, just saying that once a tank is established, and do regular WC
, it gets easier but it takes a year or two. I also dose nothing, havn't lost anything in 5-6 years. So with all that said, I would remove him, too big of a chance he won't make it. Try to take it back or give it to another established reefer with the right equipment and lighting. Get your lighting, stop dosing if you are ,do water changes and let nature take its course. it will get easier if you take your time.