Salt Bridge
A salt bridge is a hard crust that forms across the salt in a softener’s brine tank, leaving an air gap below it so the salt no longer dissolves into the water and regeneration fails.
In a water softener, the brine tank should hold salt sitting in a pool of water so the unit can draw strong brine for regeneration. Humidity, temperature swings, or the wrong salt can cause the upper salt to fuse into a solid crust. That crust bridges across the tank and holds itself up on the tank walls, while the water below dissolves the salt directly beneath it and drops away, leaving a hidden air gap.
From the outside the tank still looks full of salt, which is why a salt bridge fools people. Underneath, there is no salt actually touching the water, so the softener regenerates with weak or no brine and the resin never recharges. The symptom is hard water returning, scale and dull laundry, even though the salt level appears fine.
Breaking a salt bridge is usually a simple fix: tap the crust with a broom handle to collapse it, or pour in warm water to dissolve it. Using the right salt and not overfilling the tank keeps bridges from forming again.
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- Reverse Osmosis (RO) : Reverse osmosis is a filtration method that forces water through a fine semipermeable membrane to strip out dissolved salts, minerals, and most contaminants, producing very pure drinking water.
- Hard Water / Grains Per Gallon : Hard water is water high in dissolved calcium and magnesium, measured in grains per gallon (gpg), where higher numbers mean more scale, more soap scum, and faster appliance wear.
- Sediment Filter : A sediment filter is a mechanical filter that strains out sand, rust, silt, and other suspended particles before they reach fixtures or downstream treatment equipment.