I vacuum seal all mine that aren't being eaten fresh. I found some from 2 years ago that were hidden under some other items and they were just as I put them in there. I actually get them cold first in the fridge, blot them lightly with a paper towel then in to the bag for sealing. If you put wet fillets in, the water will get sucked in to your unit and will possibly screw it up as well as messing with the sealing line on the bag. Dry and cold works great.
Yes, I was talking to myself; sometimes even I have to ask for expert advice.