1. Evaporated Salt (The Princess of the Group)
This stuff is the purest form you can buy. It’s made by dissolving salt underground, then evaporating the water until you’re left with tiny, clean crystals. Think of it as the “sparkling water” of salts—no junk, no drama.
Side note: you’ll pay more for it, but your softener will throw a tiny party every time you pour it in. The main perk? Almost zero insoluble residue, which means your brine tank stays cleaner way longer. If you hate maintenance (who doesn’t?), this is your golden ticket.
2. Solar Salt (The Beach Bum)
Made by letting the sun and wind evaporate seawater, solar salt comes in two forms: pellets and crystals. It’s less processed than evaporated salt, which means it’s cheaper. But here’s the kicker: it can contain small amounts of sand or clay.
Different Types of Water Softener Salt & How to Choose
That grit can build up over time and gunk up your system. You know that feeling when you find a rock in your bag of spinach? Yeah, same vibe. If you go solar, at least pick the pellet version—it tends to be more uniform and dissolves more evenly.
3. Rock Salt (The Wild Card—and Not in a Good Way)
This is exactly what Dave bought: mined from underground, chunky, and dirt cheap. Let me be direct: avoid this unless you enjoy scrubbing sludge out of your tank. Rock salt can be up to 95-99% pure, but that 1-5% of insoluble junk (clay, gypsum, iron) is a nightmare.
It leaves a disgusting, brownish “mush” at the bottom of your brine tank. Over time, this can clog valves and destroy your resin bed. Is saving ten bucks worth flushing your $800 softener down the drain? I didn’t think so.
7 Best Salt for Your Water Softener System 2026 Comparison & Pros Cons
