id do a good waterchange-. Like Lupin said, a combination of some meds (espec. antibiotics) are deadly. i know popeye can be difficult to treat and can be from bacterial issues or poor water quality, aggression etc. I have used Maracyn Two before with good results and Erythromycin. then again, Maracyn that you were using should have worked too.. you may just need more time and only use the maracyn after waterchanges.
But you have already dosed the tank with alot of meds. keep in mind that using alot of meds doesn't make the disease go away any sooner, sortof like in humans--if you have a headache taking alot of ibuprofen instead of what is a theraputic level can be deadly. using more than a prescribed amount or combining antibiotics can affect the internal organs and damage them to the point where you cant save the fish.
also-keep in mind that if you dont use a hospital tank and are dosing your main tank and have a bacterial infection that MOST bacterial infections in a tank are gram negative. your beneficial bacteria is ALSO gram negative. if you dose your main tank with alot of bacterial meds you kill your BB and will cause your tank to cycle.. thats why everyone always says to use a hospital tank if your whole tank isnt affected with sickness.
test your parameters-do a waterchange and be patient. wait a few days..
btw, always do your research before getting advice from lfs-not saying they dont know what they are talking about, but you can learn far more online than they can tell you..
