If you can put all the fish in a hospital tank I would do that, keep them in the separate tank for two weeks while performing comprehensive treatment of medicine and increased temperature. With elevated temperature also in the planted tank, but no hosts, the ich will die out and the tank will be safe to return the fish to.
Ich medications containing methylene blue or malachite green will stain silicone, tubing, etc, so avoiding use of those medications in the display tank is wise. They're very effective against ich, thus using them in a separate tank is a good alternative when you can move every single fish out of the display tank.
Maximum success in treating ich means a process of treatments, versus just adding medicine once or twice. This is because of the life cycle process, so you need to hit the tank a couple of times over a time period when using something like Quick-cure. I can't speak to the salt treatment methods, as I have never used those.
From here on out though, perform a minimum two-week quarantine on all incoming fish. This way you can avoid introducing ich to your display tank again.