How regeneration works
The resin in a softener holds sodium and swaps it for calcium and magnesium as water passes. It can only hold so much. Once the beads are loaded with hardness, they stop taking any more and hard water passes straight through. Regeneration reverses the swap. The unit draws strong brine from the salt tank and pushes it through the resin. Sodium goes back on to the beads, calcium and magnesium come off, and the lot is rinsed to drain. The resin is ready again.
A manual unit does this when you turn the valve and pour in the salt. An automatic unit does it on a timer, often at night, or on a meter that counts litres and regenerates when the bed is nearly spent. A metered valve wastes the least salt and water, because it regenerates on use rather than on the calendar.
How often is set by the hardness of the water and how much the house uses. Very hard water and a large family may need it every couple of days; moderately hard water in a small flat, once a week or less. The installer sets the frequency from a hardness test, which is one more reason to have the water tested rather than guessed; the hard water signs guide covers how.
Salt: which, how much, how often
Salt is the one consumable. Use salt sold for softeners: clean sodium chloride in tablets, pellets or coarse crystals, without the anti-caking agents and iodine in table salt and without the grit in rock salt. The wrong salt does not stop the softener working, but it leaves insoluble sludge in the brine tank that eventually reaches the valve. DraQua lists a 25 kg bag of softener salt and has a guide to softener salt that goes into the types.
Keep the brine tank at least a third full and never let it run dry. An empty tank means the unit regenerates with water instead of brine, achieves nothing, and hard water comes through as if the softener were not there. Check the level once a fortnight until you know the household's pace, then as often as that turns out to need.
Two salt problems to know by name. A salt bridge is a hard crust across the tank with a hollow underneath; the tank looks full but the brine below is weak. Break it with a broom handle. Mushing is fine salt dissolving into a paste at the bottom that blocks the brine draw. Scoop it out, rinse the tank and refill with coarser salt.
Resin: how long it lasts, and what kills it
The resin bed is the softener. It lasts years, and the number of years depends on what the water carries. Chlorine in a municipal supply oxidises the beads slowly and makes them brittle. Iron and manganese in borewell water coat the beads and stop the exchange, which is called fouling. Silt and sand grind them. The signs of a tired bed are the same as the signs of a spent one: hardness in the output, and shorter and shorter runs between regenerations.
What extends it: a sediment pre-filter on the inlet, changed on time, and on iron-bearing borewell water, a resin cleaner used now and then during regeneration. If the installer fitted a standard 10-inch housing ahead of the softener, it takes a standard 10-inch cartridge; the LUXGEN Universal-Fit sediment cartridge is that part, and the fit guide explains how to check the housing before ordering. Check the size first: larger softeners often use a 20-inch or jumbo housing, which takes a different cartridge.
When the resin is done, it is replaced, not repaired. Resin is sold by the litre and a domestic bed is a modest volume, so a re-bed is a service call and a fraction of the unit's price. The cost guide has the ranges.
The maintenance checklist
| Job | How often | How you know it was missed |
|---|---|---|
| Check the salt level and top up | Every two weeks at first, then as needed | Water goes hard; scum returns in the bucket |
| Break any salt bridge | Whenever the level stops falling | Tank looks full, output is hard |
| Clean the brine tank | Once a year | Sludge at the bottom, brine draw slows |
| Change the inlet sediment cartridge | Every few months, sooner on borewell water | Pressure drops; grit reaches the resin |
| Test the output hardness | Monthly, with a drop kit | The only way to know the softener is working |
| Resin cleaner, on iron-bearing water | Per the product, during regeneration | Runs between regenerations shorten |
| Replace the resin | When output stays hard after regeneration | Regeneration no longer restores softness |
The single most useful item on the list is the hardness test. Everything else is a routine; the test is what tells you whether the routine is working. A drop-count kit costs a few hundred rupees and takes two minutes. Test the output monthly, and after every regeneration for the first few weeks. It should read close to zero. If it does not, start from the top of the list.
What goes wrong when it is skipped
The failure is quiet. No alarm, no leak. The salt runs out, the resin loads up, and the house is back on hard water without anyone noticing for weeks. The scale returns to the geyser, the shower head blocks again, the laundry stiffens, and if there is an RO purifier downstream its membrane is now taking the calcium the softener was supposed to remove. The appliance damage guide adds up what that costs.
Left longer, the damage moves into the softener itself. Dirty salt and an uncleaned tank push sludge into the injector and the valve. Fouled resin regenerates less each time until it no longer regenerates at all. A unit that would have run for a decade on a bag of salt a month becomes a re-bed and a valve rebuild. Nearly every softener that "stopped working" was starved of salt, fed bad salt, or run without a pre-filter.
Two reminders while you are at it. A softener does not lower TDS, so a TDS pen tells you nothing about whether it is working; use the hardness kit, and see the TDS vs hardness guide if that seems odd. And it does not purify: the drinking water still needs whatever the softener vs RO guide says it needs. LUXGEN makes RO purifiers and their spares, not softeners; softeners, salt and resin are on DraQua.
Questions
How often should a water softener regenerate?
It depends on the hardness and on the household's water use. Very hard water in a large house may need regeneration every two or three days; moderately hard water in a small flat, weekly or less. A metered valve decides for you by counting litres. Test the output hardness monthly to confirm the interval is right.
What kind of salt should I use in a water softener?
Salt sold for softeners: clean sodium chloride tablets, pellets or coarse crystals. Avoid iodised table salt with anti-caking agents and gritty rock salt, which leave sludge in the brine tank. Keep the tank at least a third full and never let it run dry.
How long does softener resin last?
Years, usually many. Chlorine in municipal water, iron in borewell water, and silt all shorten it. A sediment pre-filter and, on iron-bearing water, an occasional resin cleaner extend it. When regeneration no longer restores soft output, the resin is replaced.