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SEACHEM Flourish Iron (250ml,500ml)


Seachem Flourish Iron supplement results in greener leaves, stroner stems and enhances photosynthesis.

Plants that lack iron are unable to produce chlorophyll, a condition known as chlorosis, causing yellowing of the leaves. Younger leaves tend to lack iron because iron is immobile in plants, that is, plants cannot divert iron from older leaves to new ones.

Seachem Flourish Iron contains iron in a form that is readily absorbed by plants, so that the whole plant has a ready source of iron, resulting in flourishing green leaves, strong stems, and photosynthesis.

Benefits of Seachem Flourish Iron

  • Prevents yellowing of leaves
  • Results in flourishing green leaves
  • Ensures stems grow longer and stronger
  • Enhances chlorophyll production and photosynthesis

Why Flourish Iron is Unique

When choosing an iron supplement, it is important to know the distinction between the two forms of iron. The iron will be in one of two oxidation states: ferrous having a +2 charge, or ferric having a +3 charge. Ferrous iron, the preferred iron form and is soluble in water at any pH. Ferric iron, however, is only soluble below a pH of around 5.5; but if the pH is higher than 5.5, which more than likely it will be in a planted aquarium, the ferric iron will become insoluble and precipitate, settling in the root zone. Once this occurs, foliar absorbtion becomes impossible.

To overcome this precipitation, competing products employ a chelate of ferric iron: iron-EDTA. While this does keep it soluble, it has a couple of drawbacks with respect to foliar uptake of iron. (1) Iron-EDTA bonding is very strong, thus very little of the iron will be available to the plants over a given time frame and (2) Physiological energy must be expended by the plant in order to extract the ferric iron from EDTA-iron and then convert (reduce) it to the ferrous form. Our approach is different in that we use a complex (not chelate) of ferrous iron in Flourish Iron.

Flourish Iron is a highly concentrated (10,000 mg/L) ferrous iron gluconate supplement. Plants are able to much more easily derive a benet from Flourish Iron because ferrous iron gluconate is already in the ferrous form so they do not expend energy reducing it. Despite what other manufacturers may intimate, gluconate is not harmful to plants or fish. In fact, ferrous gluconate is better suited to foliar feeding than is iron-EDTA owing to the relatively weaker iron-gluconate bonding vs. iron-EDTA bonding. In addition, ferrous gluconate has the added bonus of being a source of carbon.


Use 1 capful (5 mL) for each 200 L (50 US gallons) or as required to maintain about 0.10 mg/L iron. For smaller doses please note that each cap thread is about 1 mL. Use MultiTest Iron test kit to monitor iron concentrations. Due to rapid utilization, test within 30 minutes. Use as needed to combat signs of iron deficiency (usually seen in new growth) which include: chlorosis (yellowing) of tissue between veins and short and slender stems.


Amounts per 1 g: Iron (Fe) 1%

Derived from: Ferrous Gluconate