Nitrate (NO3-)

The end product of the nitrogen cycle - much less toxic than ammonia or nitrite but still stressful at high levels.

Unit: ppm Code: NO3

📊 Ideal Ranges

Freshwater

0-40 ppm

Saltwater

1-10 ppm

Reef

1-5 ppm

Planted

10-30 ppm

📖 Overview

Nitrate is the byproduct of complete biological filtration. In freshwater fish tanks, keep under 40 ppm. In reef tanks, 1-10 ppm is ideal - too low starves corals; too high fuels nuisance algae. In planted tanks, 10-30 ppm actually benefits plant growth. The only reliable way to remove nitrate is water changes or specialized reactors.

📉 How to Lower

Water changes (still the best method). Live plants (nitrate = fertilizer). Refugium with macroalgae (reef). Deep sand bed anoxic zones. Vodka/vinegar dosing (advanced reef). Nitrate reactors.

🔗 Related Parameters

☠️

Ammonia (NH3/NH4+)

The primary nitrogenous waste of fish - highly toxic and the number one killer i...

⚠️

Nitrite (NO2-)

The second stage of the nitrogen cycle - less immediately toxic than ammonia but...