A water softener should use salt over time. The amount varies with water hardness, household use and the system settings, so the salt line may not move much from one glance to the next. But if it stays at exactly the same level through repeated regeneration cycles, the softener may not be making usable brine or drawing that brine through the resin tank.
Do not solve this by adding more salt. A nearly full brine tank can hide the problem and make inspection harder. First confirm that the salt truly is not being used, then follow the softener through one complete cycle.
Mark the salt level before assuming something is wrong
Look inside the brine tank and mark the top of the salt with painter's tape on the outside of the tank. Record the display reading and, if the controller shows it, the number of days or gallons until the next regeneration.
Check the mark again after the unit completes a scheduled regeneration. If your household uses little water or the softener has substantial capacity, regeneration may be less frequent than expected. A stable salt line between cycles is normal. A stable salt line after several confirmed cycles deserves attention.
Also check whether someone recently filled the tank. Salt pellets settle slowly and can make small changes difficult to see. Your mark gives you a better reference than memory.
Make sure the softener is actually in service
Find the bypass valve where the plumbing enters and leaves the softener. Labels and handle positions differ, so use the markings on the valve or the equipment manual rather than guessing. A unit left in bypass allows untreated water to travel around the softener. The controller may still light up and appear normal even though household water is not passing through the resin tank.
If there are separate inlet and outlet shutoff valves, confirm that both are open. Look for another pipe that could route water around the equipment. If the valve positions are unclear, take a photo and ask the installer to identify the normal service position before moving anything.
Check the display for a clock error, unplugged transformer, warning symbol or message indicating that regeneration has been disabled. After a power interruption, some controllers retain their programming but lose the correct time. That can move regeneration to an unexpected hour and make it seem as though the unit never runs.
Check for a salt bridge
A salt bridge is a hardened layer with an empty space underneath it. From above, the tank can look full even though the water below is no longer touching loose salt. Without contact between water and salt, the softener cannot make the brine needed to recharge the resin.
Press gently on several areas of the salt surface with a clean wooden handle. Do not strike the tank, and do not push hard enough to damage the salt grid or other parts below. Loose salt should shift. A broad, rigid surface or a hollow sound can indicate a bridge.
If you find a bridge, carefully break only the hardened salt layer. Remove large solid pieces if necessary. Keep tools away from the brine well, tubing and float assembly. If you cannot tell what lies below the crust, stop and have a technician clear it.
After clearing the bridge, do not expect immediate proof at the faucets. The unit still needs to make brine, complete a regeneration and flush untreated water from the home's plumbing.
Look for a solid mass of salt at the bottom
Salt can also turn into a dense paste or solid block near the bottom of the brine tank. This is different from a bridge because there may be no open cavity underneath. A flashlight may reveal murky water, compacted salt or debris around the brine well.
Do not pour in additives as a first response. The right cleanup depends on the tank design and the material inside it. Ask a provider whether the tank needs to be emptied and cleaned, whether the salt grid must be removed, and whether the brine float and pickup should be inspected at the same time.
Watch one regeneration cycle
If the salt is loose and the softener is not bypassed, observe a manual regeneration. Start it only when the drain route is secure and no one needs uninterrupted water. Use the controller instructions for your model.
You do not need to understand every display code. Watch for three basic events:
First, water should discharge through the softener's drain line during the appropriate cycle stages. No drain flow can indicate a controller, valve, drain restriction or water supply problem.
Second, the water level in the brine tank should change. Many systems add water near the end of one regeneration so it can dissolve salt before the next cycle. Others fill at a different point. The exact sequence matters, so compare what you see with the manual.
Third, during brine draw, the water level in the brine tank should go down. If water enters the tank but is never drawn out, the problem may involve the injector, air check, brine tubing, valve seals or a restriction. If water is drawn out but never returns, the refill stage may be failing.
Keep hands away from moving valve parts and do not disconnect tubing while the system is pressurized. Record the cycle names shown on the display, the approximate water level at each stage and whether water is flowing at the drain. That information can shorten a service visit.
Inspect the brine tubing without taking it apart
Follow the small tube between the control valve and the brine tank. Look for a kink, flattened section, loose connection or visible air gap where the tube should be full during brine draw. Check whether the tube was pinched when salt bags or stored items were moved.
Also inspect the brine well, usually the vertical tube inside the tank that protects the float assembly. A tilted well, stuck float or heavy salt buildup around it can interfere with filling or drawing brine.
Visual inspection is useful, but disassembly can introduce air leaks or damage small fittings. If a connection is wet, cracked or loose, photograph it and identify the replacement part before attempting a repair.
Confirm that the controller is counting water use
Many softeners regenerate according to measured water use. Run a faucet and watch the controller for a flow indicator or changing gallon count. If the display does not register flow, the meter may be stuck, disconnected or programmed incorrectly. The softener may then wait too long to regenerate, even while the household is using water.
Some units regenerate on a fixed schedule instead. For those systems, compare the programmed days with the household's actual water use and the tested hardness. Do not change capacity, hardness or reserve settings simply to force more frequent cycles. Incorrect settings can waste salt and water without correcting the underlying fault.
Use the water itself as supporting evidence
The salt line is only one clue. Check for the return of scale on fixtures, reduced soap lather or spots on glassware. If you have a hardness test kit, compare cold water from a softened indoor tap with untreated water from a known bypass or outdoor tap. Do not use a hot tap for this comparison because the water heater stores water and can blur the result.
A softener can sometimes produce soft water for a while after salt use stops because the resin still has remaining capacity. That is why the best time to investigate is when you first notice the salt level is unchanged, not after hardness has fully returned.
Know what to ask during a service call
Give the provider your observations rather than asking only for a general tuneup. Tell them whether the unit is in service, whether the meter records flow, whether the drain runs, and whether the brine level rises and falls.
Ask the technician to show you:
Whether the injector creates enough suction to draw brine, whether the brine refill volume matches the programmed salt dose, whether the meter registers actual flow, whether the control valve advances through every stage, and whether the resin tank produces soft water after regeneration.
If a part is blamed, ask for its name, the failure evidence and the result that should change after replacement. A useful checkout includes observing brine draw, confirming refill and testing the treated water. Merely starting a regeneration does not prove that the complete cycle works.
Fix the cause before refilling the tank
Once the problem is corrected, add only enough salt to maintain the level recommended for the equipment. Keeping the tank packed to the top can make bridging harder to notice and complicate cleanup.
Mark the new salt level and check it after the next regeneration. Confirm that the household tap tests soft and that the brine water follows the expected rise and fall. Those three checks provide better proof than the controller display alone.
If you need a company to diagnose the system, use the Missouri Water Experts directory to compare providers. Describe the symptoms when you call and ask whether the service visit includes brine-cycle observation and a treated-water test. The goal is not simply to make the salt disappear. It is to confirm that the softener measures water use, makes brine, draws it through the resin and returns to service correctly.