You can mix pimafix and melafix. Sounds like the fish with the slime would of benefit from that. As far as ICH goes, you would need to treat it with a copper based product OR hyposalinity but NOT BOTH AT THE SAME TIME or it would kill your fish. How long has your tank been up?
Here is something I read: With both of these medications, they only kill off some bacteria but not all. When added to your main tank, your good bacteria will actually feed off of it resulting in a large bacteria bloom and lowering dissolved oxygen. The fish would start breathing rapidly because the oxygen in the tank is going down resulting in possible death. You would need to increase your oxygen levels and make sure you get lots of water movement towards the top of your tank so to promote good aeration.
, I would use a cheap little QT tank (good to keep on hand) and a cheap filter from Walmart or something minus carbon of course. If you had ich as well, you will need this to house any fish you have for a few weeks if you want to get rid of it in your main tank.