Fluval 107/207 Nitrite Remover (3-pack) – A set of filter media pouches compatible with Fluval 107 and 207 canister filters, formulated to eliminate nitrite in aquarium water. These specialized resin or chemical media packs absorb nitrite—a toxic byproduct of the nitrogen cycle—to help maintain safe water conditions, especially in newly cycled or heavily stocked tanks. Regular use assists in keeping nitrite levels at zero, protecting fish from nitrite stress or poisoning.