I didn't even see your response till now. I'm having issues with my phone. Keeps saying I can't connect to the server on here and has posted my response multiple times even though it would just shut down my app. Thanks for your response, everyone has given very helpful info! I have camden tablets from probably 10 or so years ago when I first bought brewing equipment. It's unopened, and has no expiration date. Do they go bad??
Yes, they go bad. Well not "go bad", but lose effectiveness.
Once the wine is totally clear, and no longer dropping ANY lees at all after at least 60 days in a new carboy, it's ready to be stabilized.
Using 1/2 teaspoon of sorbate per gallon of wine, and 1 crushed campden tablet per gallon, both dissolved in a little water, put that in the new vessel and rack the wine into that. Let it sit about 3 days (minimum). If it remains clear, and no new lees fall, you can sweeten the wine to taste. Once the wine is sweetened to your satisfaction, let it sit a few days to ensure that no new fermentation starts. If it remains clear, and no signs of fermentation have started, you can proceed with bottling.
It's really easy, but time is important here. The wine must be finished fermenting, and totally clear. That's because of what sorbate actually does. The way it works is that sorbate does not kill yeast, but it prevents yeast reproduction.
So, in an active fermentation when there are hundreds and hundreds of billions of active yeast, it won't do a thing. But once fermentation stops, and the wine clears, and the wine is racked off of the fallen yeast, it can be added to prevent yeast reproducing, thereby not allowing fermentation to begin again (usually). Sorbate works better in the presence of sulfite (campden), so they are generally added together.
However, it will NOT stop an active fermentation and will not work in a wine that is not clear and done fermenting. That's why it's important that the wine is clear, no longer dropping any lees at all, and ready to stabilize before sweetening and bottling.