During a service run of a water softener, a certain amount of hardness exits the resin bed with soft water. This is what leakage is. Leakage occurs as a result of hardness ions being left in the bed or by channeling the water through the resin bed. Some causes of leakage are:
- The amount of hardness and/or total dissolved solids in the brine used for regeneration. For this reason, brine should be made with softwater.
- The effectiveness of the regeneration which could be a function of the salting rate, fouling of the resin beads or poor quality brine.
- The flowrate through the water softener could be too high.
As a general rule, the higher the TDS in the brine, the greater the leakage and lower resin capacity.