Seachem Flourish Iron Iron Supplement 500ml

Iron is fixed in plants. This means that plants cannot transfer iron from old leaves to new ones. Therefore, deficiency symptoms first appear on new or young leaves. Because plants use iron to produce chlorophyll, a lack of iron can lead to chlorosis or yellowing of young leaves. Stems may also appear short and slender. If the deficiency is severe and chronic, each new leaf will be lighter in color than the previous one.

When choosing an iron supplement, it is important to understand the difference between the two forms of iron. Iron will be in one of two oxidation states: ferrous, which has a +2 charge, or iron, which has a +3 charge. Ferrous iron, the preferred form of iron, is soluble in water at any pH. However, ferric iron only dissolves below pH values below 5.5. But if the pH is above 5.5, which is likely in a planted aquarium, the ferric iron will become insoluble and precipitate, precipitating in the root zone. Once this happens, foliar absorption becomes impossible.

To overcome this precipitation, a competing product uses a ferric chelate: iron EDTA. While this does keep it soluble, it has several disadvantages in terms of foliar uptake of iron. (1) The binding of iron to EDTA is very strong, so there is very little iron available to plants in a given time frame; (2) plants must consume physiological energy to extract ferric iron from EDTA. iron, which is then converted (reduced) to its ferrous form. Our approach differs in that we use a complex (not a chelate) of ferrous iron in Flourish Iron™.

Flourish Iron™ is a highly concentrated (10,000 mg/L) ferrous gluconate supplement. Plants can more easily benefit from Flourish Iron™ because the ferrous gluconate is already in the ferrous form, so they don't expend energy to reduce it. Although other manufacturers may suggest that gluconate is not harmful to plants or fish. In fact, ferrous gluconate is more suitable for foliar feeding than ferric EDTA because ferric gluconate binds relatively weakly to ferric EDTA. In addition, ferrous gluconate has the added benefit of being a carbon source.

Instructions:
Use 1 cap (5 mL) per 200 liters (50 US gallons), or maintain about 0.10 mg/L iron as needed. For smaller doses, note that each cap thread is approximately 1 mL. Iron concentrations were monitored using the MultiTest™ Iron Test Kit. Tested within 30 minutes due to quick use. Use as needed to combat signs of iron deficiency (usually seen in new growth) including: chlorosis (yellowing) of the tissue between veins and short, slender stems.