Imagine you’re making a giant, salty soup. You want enough salt so the water can get nice and saturated, but not so much that it piles up into a solid mountain. Never fill it past the top of the water level. That’s my golden rule.
Check the water level inside the tank. It should be a few inches from the top. Then, drop salt until it sits just above that water line. Presto. You’re a salty genius.
If you fill it to the brim, the salt can “bridge” (form a hard crust) or “mush” (turn into sludgy goop). Both are gross and annoying.
The “Less is More” Trap
Some folks think using less salt saves money. Spoiler: It doesn’t. Saving salt is like saving toothpaste. You end up with a half-done job and hard water spots that make you weep.
Most standard tanks hold between 150 and 300 pounds of salt. You do not need to use that much at once. Just fill it halfway every month or two.
Water Softener Add Salt To Water at Wilda Talley blog
Check the salt level monthly. If you see the brine tank looking like a ghost town, it’s time to restock. Your softener will start screaming (metaphorically) for more salt.