Fluval A-1502Safe for fish and plantsDoes not contain phosphates, will not affect pH or hardnessResin can be recharged several timesRemoves up to 25 mg/L (ppm) of nitrate in a 50 gallon aquariumFor freshwater use onlyFluval Lab Series Nitrate Remover is a high capacity laboratory developed ion exchange resin. Developed from a pure High Grade Strong Base Anion Exchange resin, Nitrate Remover rapidly and selectively removes nitrate and eliminates toxic nitrite in a matter of hours, resulting in a healthy environment for your fish.