Sorry you're going through that- it's such a pain. Unfortunately, things like Quick Cure aren't good for a reef tank (or even live rock for that matter).
We're quite limited when it comes to corals and inverts and you'll probably receive various opinions. So here's my opinion.

If you want to treat your main tank, without a QT, there are a few things you could choose to do.
Hyposalinity, copper and formalin are out. You could try one of those "reef-safe" meds like Kick Ich- there are many out there. Of course, some people say they don't work at all, while others claim to have success- so it's really up to you if you want to purchase one of these.
You can purchase a crew such as cleaner shrimp, cleaner gobies, and/or cleaner wrasse (cleaner wrasse are a controversial addition to a home aquarium and not as highly recommended as they once were). You can also try freshwater dips if you're able to catch any of your fish. Some give the freshwater dips with Quick Cure as well.
You can also purchase a UV sterilizer and/or diatom filter. While not a 100% cure, they can kill the ich in it's free-swimming stage.
You can also try to feed your fish garlic or garlic supplements, such as garlic xtreme. It entices some fish to eat and many believe it to help boost their immune system (I give my fish this whether or not they have ich) to overcome the parasite.
How long have you had the ich? Sometimes it'll just go away by itself. Do you know what stage it's in?
I only had to get saltwater ich once before I decided to purchase a QT tank (when I first began) however, some people don't feel it's feasible breaking down their entire tank to catch the fish.
It really comes down to how you feel like approaching this and what methods are suited for you with what you're willing to try.
Let us know what happens!