Ion Exchange Resins & Water Softener Salt

How ion exchange works

Ion exchange resins are tiny plastic beads that hold charged groups on their surface. As water flows through a bed of resin, the beads swap one kind of dissolved ion for another:

• In a softener, a cation resin in the sodium form swaps calcium and magnesium (hardness) for sodium. When the resin is exhausted, brine made from softener salt regenerates it.
• In a demineralisation (DM) plant, a cation resin in the hydrogen form removes all cations, and an anion resin in the hydroxide form removes anions such as chloride, sulphate and silica, producing very low-TDS water. These are regenerated with acid and caustic.
• A mixed bed contains both cation and anion resin for final polishing to very high purity.

Our resin range

Signs your resin needs attention

• Soft water output per regeneration keeps falling.
• Hardness or TDS breaks through soon after regeneration.
• Pressure drop across the vessel has increased.
• Resin beads appear in the outlet, or the resin looks broken, dark or fouled.
• The resin is many years old or has been exposed to chlorine or iron.

Chlorine, iron and oil damage or foul resin. Good pre-treatment with activated carbon and iron removal media makes resin last much longer.

How much resin do you need?

1. Check the vessel: diameter and height, or the litres of resin specified on the softener or DM unit.
2. Know your water: total hardness for softeners; full analysis including silica for DM plants.
3. Know your demand: litres of treated water per day and how often you want to regenerate.
4. Send us the details: we suggest the resin type and quantity in litres or bags.

Who uses our resins

• Homes, villas and apartments
• Hotels and hospitals
• Laundries
• Boiler feed water
• DM plants in pharma, chemicals and power
• Electroplating and electronics
• Battery water and labs
• Water treatment OEMs and AMC contractors

Ion Exchange Resins: product range

Each product line has its own page with uses, dosing guidance and FAQs.

• Water Softener Resin
• DM Plant Resins (Cation and Anion)
• Mixed Bed Resin
• Softener Salt Tablets

Frequently asked questions

What is ion exchange resin used for?

Ion exchange resin is used to soften water by removing calcium and magnesium, and in demineralisation plants to remove almost all dissolved salts. It is also used for polishing high-purity water.

How long does water softener resin last?

Softener resin can last many years with good pre-treatment. Chlorine, iron, oil and very frequent regeneration shorten its life. Falling output per regeneration is the usual sign that it needs replacing.

What is the difference between softener resin and DM resin?

Softener resin is a cation resin in the sodium form that swaps hardness for sodium and is regenerated with salt. DM plants use a cation resin in the hydrogen form and an anion resin, regenerated with acid and caustic, to remove almost all salts.

Which salt should I use for a water softener?

Use clean softener salt or salt tablets made for brine tanks. Impure salt can leave sludge in the brine tank and foul the resin.

Does a water softener reduce TDS?

No. A softener swaps hardness for sodium, so TDS stays about the same. To reduce TDS you need reverse osmosis or a DM plant.

Can I replace the resin in my softener myself?

Many people do, but take care to keep the distributor intact, fill the right quantity, and backwash and regenerate before use. Tell us your softener model or vessel size and we will suggest the quantity.

What causes resin to turn brown or black?

Usually iron or organic fouling, or damage from chlorine. Iron removal media and activated carbon before the softener help protect the resin.