If you have any pictures they can help.As far as slime on the fish it may be in relation to a parasite but not always. I have used quick cure for some time without any ill effects as long as using the directed amounts,I even use it in half dose as a preventative treatment on new arrivals. So on that note it will not hurt to half dose the QT tank with the quick cure as well as add some aquarium salt to aid in fighting the parasite\infection.Keep the water clean with appropriate water changes and he should get better provided it is a parasite the product targets. If in doubt you may want to ask the pet store about the condition of the fish,I know dale can do slime coat analysis under a microscope if things get bad and you need to know whats going on.Good thing you have a Quarantine tank,makes life easier.You may want to half dose the pike cichlid as well.What kind of pike cichlid did you get?