Ok here is a great article on QT
You need to get as large as possible. I think a 15g would be fine, a 10 is better than nada.
You can use water straght from your main tank to start the qt
. Yes it has ich, but so does your fish. The med will kill it soon enough. If you have a sponge or something that has been in the main, you can use that to help also. Just to warn you, your water changes will be about everyday. You will have high water readings on your test. You must be consistent with the water changes.
What method of treatment will be using?
It is going to be a chore, but it will be well worth it. Just remember to keep them in at least 4 weeks, 6 weeks is better. From here on out make sure you qt
all new additions, and you can keep ick out of your tank!!