You'd only need to salt it or put it in borax if it had a lot of flesh on it. I've used frozen ones from last year that worked fine. For that matter, good or bad I've used a whole duck from last year. Saved it because it was too shot up to eat.
I'm using the freezer, no salt. Another good tape to use is electrical black tape. It is smaller and you can stretch it easier to get it a good tight hold. But I am guessing it is not as good a duct tape in the water