Ion exchange resin to remove nitrate from fresh water and slightly brackish water - the resin can be regenerated after loading with a saline solution. The resin is ready for use and can be used immediately in a filter.
The aquarium water flows through a filter containing the nitrate resin. The nitrate in the water is exchanged in the ion exchanger for chloride ions. When the capacity is exhausted - the nitrate concentration in the aquarium water slowly increases again - the resin can be regenerated.
A saline solution is prepared for this purpose. Dissolve approx. 300 g/l iodine-free common salt (NaCl) per liter of tap water (approx. 30°C); tablet salt from softening systems can also be used. Approx. 5 liters of brine are required per liter of nitrate resin. (If you have a softening unit, you can use the brine from this unit directly).
Remove the nitrate filter with the resin from the aquarium system. Allow the brine to run slowly through the filter in the opposite direction to how it runs in normal operation. Then rinse the resin slowly with approx. 10 liters of tap water per liter of resin to prevent common salt from entering the aquarium. If you have a conductivity meter, you can also rinse until the outgoing water has the same conductivity as the incoming water.
Install the filter back in your aquarium and put it into operation.