Here is a link to an item that should be on everyones list. I came across it during a visit to a gun show in my area a few months ago. It was meant to be in a bug out bag but my first thought was to have this on the boat.
It is called Oral IV
https://www.amazon.com/gp/product/B00I9672Z8/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

I ordered this pack of 25 and I'm going to bring this as a preventative measure to being in the sun all day. I have Yeti's for the crew and will keep them full of ice-water and we will all take one of these Oral IV's as an Aperitif before dinner LOL
Captain Redbeard