Just to add to what Roger said...
If this is a permanent qt I suggest painting the back and sides blue. A cheap reef background taped on would be a better option. Paint the bottom white or tape on white construction paper. Pick up some cheap fake silicone corals and pvc fittings for hiding. Black or grey pvc would be best, but white is ok. Basically my philosophy is to try and recreate a reef environment. This will help to make the fish feel more comfortable rather than sitting in a bare tank with nothing but pvc and equipment. Many fish have been lost in qt from just stress alone and no disease. I think a couple bucks to try and make it look halfway like a reef is advantageous.
As far as equipment, I use a cheap bio wheel filter, a powerhead and a nano air stone skimmer. The skimmer is only for the observation period. You don't want to use it in conjunction with medication as it will remove the meds. Pick up a bundle of quilt batting and rubberband it to the plastic filter pad in the bio wheel after you have exhausted the original filter. This will save you some money down the road. In fact it's so cheap I just discard the old one once every few days. Especially if using a med that will kill the bacteria anyways. Be sure to remove any carbon from the original filter pad. I only use a heater in the winter. Any light will do and I would use one. Again, strive to make the environment as natural as possible.
As far as medications go. Always dose your waterchange water. And be sure to top of with fresh rodi water daily. Monitor ammonia daily and perform water changes if detected. Always have a batch of seawater mixed and ready to go. No other life should be present in the tank, ie, clean up crew. However, if compatible I think it's a good idea to qt 2 fish at a time, especially if one is a finicky eater. The company of the fish that is more likely to eat may encourage the other to eat.
That's all I can think of at the moment. Good luck.
Btw, your display needs to go fallow for 72 days to eliminate the ich that has now compromised the system.
