Flourish Iron

Seachem Flourish Iron is a highly concentrated (10,000 mg/L) ferrous iron gluconate supplement, specifically designed for delicate planted aquariums. Plants use iron to produce essential chlorophyll. An iron deficiency causes chlorosis, which is a yellowing of young leaves, often accompanied by short, thin stems. If this deficiency persists, each new leaf will appear paler than the last.

Plants assimilate this formula more easily because ferrous iron gluconate is already in the ferrous form (Fe²⁺), which prevents plants from expending energy to reduce it. Conversely, ferric iron (Fe³⁺) is only soluble at a pH below 5.5, which is well below common levels in planted aquariums, making it ineffective.

The ferrous iron in Seachem Flourish Iron is therefore the preferred form of iron: it is soluble at all pH levels and is an excellent carbon source, making it versatile and suitable for various water parameters. In addition, ferrous iron gluconate is better suited for foliar absorption than iron-EDTA, allowing plants to grow and develop more quickly.