As for the popeye,you can use maracyn with live rock but you can kiss all your nice colors goodbye.As for the ick on your tang,been there!!Since you can't use any copper with live rock,this could get rocky.You will get different answers to how to treat it from everyone.I like greenex myself for help in preventing disease.I use about once a week.But when I HAD ick,I used a medicine called oomed.There are a lot of different ones people here had mentioned to use,but I couldn't find them around here.So I simply went to the lfs and asked for a reef safe treatment.It worked great.But if you do that,make sure that store is reliable as some don't know what they are talking about.If you plan to use maracyn,let me know because there are a few things you should do if you treat with it.