Special nitrate nutrition for aquarium plants. Measure Nitrate levels with the Flora Nitro test and add Nitro nutrient as needed. Colombo Nitro, Phospho and Ferro tests and nutrition have been developed especially for Aqua Scapers. Contents: 250 ml. Dosage: 1x pump (1.25 ml) per 25 litres of water increases Nitrate levels by 2.5 mg/l.