Filter Media & Cleaning

API Nitra-Zorb

RechargeableFreshwater

API Nitra-Zorb is a pouch of natural and synthetic ion-exchange resins that selectively remove ammonia, nitrite and nitrate from freshwater aquariums. It sits in the filter’s water path and takes the toxins out of the water directly, which makes it a safety net for a cycling tank, a fix for a nitrate reading that will not come down, and a way to bridge a filter that has been disturbed. When it is saturated you recharge it in a solution of API Aquarium Salt and use it again; a pouch is replaced after about two months. It is phosphate-free and for freshwater only.

View at Jungle Aquatics

Live pricing and stock on jungleaquatics.com — purchase through Jungle Aquatics, with delivery across South Africa.

Dosage calculator

Enter your aquarium volume and the calculator works out how much API Nitra-Zorb to use for each rate on the pack.

Aquarium volume

Measured in

Use the water the tank actually holds, less substrate and decor.

Pouches needed1 pouches per 210 litres
Enter a volumeRecharge every 5 days to 2 weeks; replace the pouch after 2 months

Recharge in 80 g of API Aquarium Salt dissolved in 240 ml of warm water, soaking for 2 hours.

A guide only — always follow the dosing instructions printed on the pack, and measure with the bottle's cap or a syringe rather than by eye.

Technical details

Product type	Ion-exchange resin pouch
Removes	Ammonia, nitrite, nitrate
Suitable for	Freshwater aquariums only
Rechargeable	Yes — 80 g API Aquarium Salt in 240 ml warm water, soak 2 hours
Recharge schedule	Every 5 days in a new tank or when toxins are detected; every 2 weeks once established
Lasts	Replace the pouch after about 2 months
Fits	About 18 × 17 cm pouch — canister baskets and hang-on filters
Phosphate	Phosphate-free
Made by	Mars Fishcare, USA

Nitra-Zorb is for temporary use alongside normal media, not as the only filtration in a tank.

How do I recharge Nitra-Zorb?

Dissolve 4 tablespoons (80 g) of API Aquarium Salt in 240 ml of warm tap water, rinse the pouch, and soak it in the solution for 2 hours. Rinse it lightly under the tap and put it back in the filter. How often depends on the tank: in a new aquarium, or whenever ammonia or nitrite shows on a test, recharge every 5 days for the first month and every two weeks in the second; in an established tank, every two weeks. If you are using it to bring nitrate down, recharge every 5 days until the reading is 20 ppm or less. Keep the pouch in the recharging solution when it is not in use, and replace it after about two months.

Takes the toxins out, rather than waiting for bacteria

A biological filter removes ammonia and nitrite only as fast as its bacteria can grow. Nitra-Zorb removes them by ion exchange the moment water passes through the pouch, which is why it is so useful in a new aquarium, after a medication course, or whenever a test kit shows a reading that should be zero.

Recharge in salt, reuse, replace at two months

Dissolve four tablespoons (80 g) of API Aquarium Salt in 240 ml of warm tap water, soak the pouch for two hours, rinse lightly and return it to the filter. In a new tank or when ammonia or nitrite is present, recharge every five days for the first month and every two weeks in the second; in an established tank every two weeks. Store an idle pouch in the recharging solution.

The nitrate lever

When nitrate is the problem, recharge every five days until the reading is 20 ppm or lower, then drop back to the normal schedule. It is a complement to water changes, not a replacement for them, and API is clear it should not permanently replace other filter media.

Frequently asked questions

Can I use Nitra-Zorb in a saltwater tank?

No. The resins are selective for freshwater; in salt water they do not work. It is a freshwater-only product.

Will it fit my filter?

The pouch is about 18 × 17 cm and flexible, so it sits in a canister basket or behind the cartridge of a hang-on filter. For a very small filter you can open the pouch and use part of the contents in a media sock.

Can it replace my other filter media?

No. API describes it as a temporary aid to be used alongside the normal mechanical and biological media, not instead of them.

Does Nitra-Zorb add phosphate?

No. It is completely phosphate-free, so it will not feed algae.

Is API Nitra-Zorb available in South Africa?

Yes — Jungle Aquatics in Fourways, Johannesburg stocks it, along with the Aquarium Salt to recharge it, and delivers nationwide; live pricing and stock are on jungleaquatics.com.

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South Africa's leading pet and aquarium store since 2007 — with the API range on the floor in Fourways, advice from people who test water every day, and easy ordering from anywhere in the country.

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