So -- my 5-gallon sprayer is mounted on my trailer. I often leave roundup in the sprayer overnight if I'm going to be using it the next day. The trailer stays outside so I need to figure out how to stop the roundup from freezing inside the sprayer. I thought about anti-freeze --- but I figured that probably wasn't very wise. I think rubbing alcohol lowers the freezing point of a liquid but I don't know if that's any smarter than anti-freeze. It's a huge PITA to remove the liquid every single night. It's also a huge PITA to bring the sprayer inside every night. Anyone have any ideas? -- Thanks.