Nitrate Resin for Koi Ponds

Nitrate resin for targeted nitrate removal

Elevated nitrate levels are particularly common in heavily stocked koi ponds. Feeding, fish waste and the decomposition of organic matter continuously produce nitrate. At the same time, many koi ponds contain too few aquatic plants to absorb these nutrients naturally.

This high-quality nitrate resin has been developed for the targeted removal of nitrate from pond water. It is a nitrate-selective, strongly basic and macroporous anion-exchange resin. The resin exchanges nitrate ions in the water for chloride ions, thereby reducing the nitrate level without significantly altering the pH value.

Ideal for koi and fish ponds

The nitrate resin is particularly suitable for:

• heavily stocked koi ponds
• ponds with little or no planting
• quarantine and holding tanks
• filter systems with good water flow
• ponds with consistently elevated nitrate levels

By selectively binding nitrate, the resin can help stabilise water quality in ponds with a high biological load.

High absorption capacity

One litre of nitrate resin can absorb up to 30 grams of nitrate. The actual service life depends on the nitrate concentration, pond volume, fish stock, feeding levels and the amount of resin used.

As a guideline, approximately 1 litre of nitrate resin is recommended per 1'000 litres of pond water. A smaller quantity can also be used, but the resin will need to be regenerated more frequently.

Easy to use in the pond filter

The nitrate resin has a fine grain size of approximately 0.4 to 0.6 millimetres. It must therefore be placed in a suitable fine-mesh filter media bag to prevent loss of material.

Position the filled filter bag in an area of the pond filter where the water flows evenly and passes through as much of the resin as possible. Good water circulation improves nitrate removal and allows the filter medium to be used more efficiently.

For particularly accurate monitoring, the nitrate resin can also be installed in a separate bypass. This allows the nitrate level to be measured before and after the resin, making it easier to determine when regeneration is required.

Regenerable and reusable for several years

Once the absorption capacity of the resin has been exhausted, it can be regenerated using a solution of common salt and then reused.

For each litre of nitrate resin, use:

• 200 to 250 grams of common salt
• 2 litres of warm water at approximately 40 °C
• a regeneration period of approximately 10 to 12 hours

For effective regeneration, the salt solution should be circulated or regularly moved through the resin. After regeneration, rinse the nitrate resin thoroughly with clean water before returning it to the pond filter.

When used and regenerated correctly, the resin can be reused for several years.