I like pickles for hydration. They are basically zero calorie, savory, and pack a ton of salt. Most hydration stuff out there is sweet and on a long day sometimes you need something to break up the sweet fitness snacks.
Yup, that was exactly the thing I was going to say.
The little convenience store nearest the gym I used to go to sold the hell out of them. When there was a road crew working in the area, we couldn't get them because they were always sold out.
When I started martial arts, there was a small batch of us that would stop at a different shop on the way in and grab a big pickle and a small beer for after class. That combination worked so good after a serious workout where you'd end up throwing up from the intensity. Which seems crazy, but it was way better than the usual drinks and snacks sold for replenishment.