FERMENDO Nitrate resin for removal of nitrate

18,95 24,00 

Includes 19% VAT
Delivery Time: sofort lieferbar
Additional duties, taxes and fees may apply for deliveries to non-EU countries.

1 litre nitrate resin for 250 litres aquarium water


FERMENDO Nitrate resin for removal of nitrate

This selective anion exchange resin is a strongly alkaline anion exchange resin which is used to remove nitrate or nitrite from the aquarium water. FERMENDO nitrate resin acts as an anion exchanger resin in chloride form (Cl-) and is approved for use in food and drinking water applications. FERMENDO nitrate resin can be easily and effectively regenerated with commercially available iodine-free common salt.

The resin supplied by us is selective and essentially only filters nitrate from the water, the remaining water values are not changed. It keeps the bound nitrates even when saturated and, unlike many other resins, does not release them back into the aquarium or pond water when saturated.

Instruction manual:
Place the resin in a fine-meshed bag, such as a pair of women’s fine pantyhose (80 DEN) or a special bag for nitrate resin, and hang it in the water flow. Alternatively, you can place the resin in your filter, then in the last filter stage, before the water flows back into your aquarium.

The water must flow well through the bag so that the nitrates can be absorbed by the resins.

When the resin is saturated, it no longer absorbs nitrate and the nitrate level of the water increases. If nitrate is measurable in water, the resin is probably saturated and needs to be regenerated.

Regeneration of 1 litre nitrate resin:

  • Dissolve 300 g iodine-free salt in 3 litres lukewarm water in a bucket
  • Place bag of nitrate resin in bucket with salt solution
  • Aerate the solution with a diaphragm pump and an air stone
  • After 24 hours, the water in the bucket has a brown-black color like coffee*
  • Rinse the resin under running lukewarm water and put the resin back into the filter.

*When the water in the bucket quickly becomes dark, it is advisable to prepare a new salt solution after 12 hours. You can then let this solution act on the resin for another 12 hours.

Resin regeneration is required approximately every 2 to 6 weeks, depending on the amount of nitrates to be filtered.

Please pay attention:

  • Remove the nitrate resin from the aquarium or pond when treating the fish with salt. If you leave it in, it would be similar to the process of resin regeneration, because it will release all nitrates absorbed with a nitrate peak.
  • The nitrate resin must also be removed when drugs are used, otherwise the drugs will be filtered out of the water and the treatment will not work.
  • After regeneration, the resin must be kept moist, it must not dry out (the supplied bucket may be used for storage, for example).
  • The nitrate resin should always be regenerated with iodine-free salt.


Delivery quantity: 1 litre nitrate resin, sufficient for 250 litres aquarium water

For sustainability reasons, we offer the resin in a small bucket which, unlike a PE bag, can also be used for other purposes. The resin can also be stored there safely and moist after regeneration when it is not in use.

Additional information

Weight 0,89 kg
with or without resin bag

without filter media bag, with filter media bag