API Nitrite Test Kit Freshwater/Saltwater

• Reads nitrite 0–5.0 ppm – covers the full range a new or disturbed tank can spike to.
• Fresh and saltwater – one reagent, one procedure, either water type.
• About 180 tests per kit – enough for daily testing through a full cycling period with plenty left for ongoing monitoring.
• Fast liquid test – add reagent to a 5 mL sample, shake, wait five minutes, read against the chart.
• Colour card reads in ppm steps – lets you track whether a spike is rising or falling, not just whether it's present.

Following API's testing procedure:

1. Fill the supplied test tube to the 5 mL line with a water sample.
2. Add Nitrite Test Solution – see the instruction booklet for the exact drop count.
3. Cap and shake for the specified time.
4. Wait five minutes for the colour to fully develop.
5. Compare the sample against the colour card in good natural light.

Test every other day while a tank is cycling, when nitrite is most likely to spike, and weekly once the biological filter is established – typically four to six weeks after setup.

Included:

• Nitrite Test Solution reagent bottle
• Capped glass test tube
• Colour comparison card
• Instruction booklet

Not included:

• A reference or calibration standard
• Any treatment for correcting a positive reading

Any nitrite reading above zero calls for an immediate water change to dilute it, and a check of what disturbed the biological filter – a substrate clean, a filter media change or a new fish load are the usual causes. In freshwater, a small dose of API Aquarium Salt reduces nitrite's toxicity to gills while the filter catches up; it does not remove nitrite itself. API Quick Start adds live nitrifying bacteria to help re-establish the biological filter after a spike.

Retest daily until the reading returns to zero, and check ammonia at the same time – a nitrite spike often follows an ammonia spike as the same cycling fault.

Suitable for:

• New tank cycling, where nitrite is the second stage to test for
• Diagnosing fish gasping at the surface or gill damage with no obvious cause
• Fresh and saltwater fish-only and community systems

Not suitable for:

• Measuring ammonia or nitrate – API sells separate kits for each stage of the cycle
• Ongoing daily use once a tank is fully cycled and stable – weekly testing is enough

As with any liquid reagent test kit, keep the solution away from children, avoid contact with skin and eyes, and follow the instruction booklet if the reagent is splashed or swallowed.

• API Ammonia Test Kit Fresh/Saltwater – the stage of the cycle that usually spikes just before nitrite does.
• API Freshwater Master Multi Test Kit 5 in 1 – tracks nitrite alongside pH, ammonia, nitrate and KH in one kit.
• API Aquarium Salt – reduces nitrite's toxicity to gills while a spike is brought under control.
• API Quick Start – live nitrifying bacteria to re-establish the biological filter after a spike.

This is a consumable test kit, so no manufacturer warranty period applies. That does not affect your rights under the Australian Consumer Law: if the product is faulty, unsafe or not as described, you are entitled to a remedy.

Ships as standard freight.

Does this kit test freshwater and saltwater tanks?

Yes. API rates the same reagent and procedure for both water types.

How many tests are in one kit?

Approximately 180, based on API's published pack count. Actual test count can vary slightly with sample technique.

Why is nitrite dangerous if I can't see or smell it?

Nitrite crosses fish gills and interferes with oxygen transport in the blood, a condition sometimes called "brown blood disease." Fish can be visibly stressed or gasping well before the water looks or smells any different, which is why testing rather than observation is the reliable way to catch it.

How often should I test for nitrite?

Every other day while a tank is cycling, and weekly once the biological filter is established, typically four to six weeks after setup.

Does salt actually remove nitrite?

No. Salt reduces nitrite's toxicity to fish gills by competing for uptake, but it does not remove nitrite from the water. A water change and restoring the biological filter are what bring the reading back down.