Yes, a quarantine tank is a good idea. Snail rid, not so much. It's copper based, which is bad for plants and all inverts. It can harm your plants, and if you have inverts like shrimp in your tank, it can kill them if they nibble on the plants.
Aside from that, it's not the snails you want to get rid of in the quarantine, it's the potential disease and parasites that can be living on the plant.
There are two different dips that you can make to clean your plants. One is a mild bleach solution. This can kill some plants, though. Once you're done with the dip, put it in a bucket with some water and a lot of dechlorinator, and you're good.
The other is PP (I think potassium permagnate). It's a bright purple stuff they sell at the hardware store. If you do a search, you'll be able to find how to mix a solution for a plant dip. (Or someone might come around here and let you know)
