Seachem Flourish Iron – Ferrous Iron Supplement to Stop Plant Chlorosis

Green Up Yellowing New Leaves Fast

When your plants push out pale, yellowing new leaves with short, slender stems, they're starving for iron, and iron is immobile so the newest growth suffers first. Many iron products lock the iron in a form your plants can barely use.

Seachem Flourish Iron is a highly concentrated (10,000 mg/L) ferrous iron gluconate supplement. Because it's already in the plant-preferred ferrous form and soluble at any pH, plants absorb it easily without spending energy converting it, unlike the iron-EDTA chelates competitors use. The gentler iron-gluconate bond makes it better suited to foliar feeding, and it even adds a source of carbon, all while remaining safe for plants and fish.

Flourish Iron is formulated by Seachem Laboratories, the chemistry-driven aquatics company founded in 1979 in Madison, Georgia, where in-house chemists develop each product. It's the targeted iron supplement of the coordinated Flourish planted-tank system, filling a specific micronutrient gap alongside Flourish Excel's carbon, the comprehensive Flourish supplement, and dosing of nitrogen, phosphorus, potassium, and trace elements.

1. Use 1 capful (5 mL) per 200 L (50 gallons), or as needed to maintain about 0.10 mg/L iron.
2. For smaller doses, note each cap thread is about 1 mL.
3. Monitor with MultiTest: Iron and test within 30 minutes due to rapid utilization.

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What It Does

A highly concentrated (10,000 mg/L) ferrous iron gluconate supplement. Ferrous iron is the plant-preferred form and is soluble at any pH, so plants derive benefit easily without expending energy to reduce it. The relatively weaker iron-gluconate bond makes it better suited to foliar feeding than iron-EDTA, and ferrous gluconate also provides a source of carbon. Safe for plants and fish. Combats iron deficiency signs such as chlorosis (yellowing) between veins and short, slender stems.

Directions

Use 1 capful (5 mL) for each 200 L (50 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.

Guaranteed Analysis

Iron (Fe) 1%

Ingredients

Derived from: Ferrous Gluconate

Available Sizes

250 mL, 500 mL

Why Seachem Flourish Iron

• Targeted iron dose in the Flourish system: lets you correct iron independently of your other nutrients, complementing the comprehensive Flourish supplement and the rest of the coordinated line.
• Plant-preferred ferrous form: already ferrous and soluble at any pH, so plants absorb it directly without spending energy reducing it, unlike iron-EDTA chelates.
• Fixes iron chlorosis: restores the immobile iron that leaves the newest growth pale and yellow between the veins with short, slender stems.
• Highly concentrated: 10,000 mg/L of iron, dosed at 1 capful (5 mL) per 200 L (50 gallons) to maintain about 0.10 mg/L.

Best For

Ideal for both low-tech and high-tech planted tanks showing iron deficiency, and especially valuable in high-light, fast-growing setups and red or color-forming plants that draw down iron quickly. Best when new leaves emerge pale or yellow between the veins and you need to top up iron without disturbing your NPK balance.

FAQ

Why ferrous gluconate instead of iron-EDTA? Ferrous iron is the plant-preferred form and is soluble at any pH, so plants benefit without expending energy to reduce it, and the weaker iron-gluconate bond suits foliar feeding better than iron-EDTA.

How do I dose and monitor it? Use 1 capful (5 mL) per 200 L (50 gallons) to maintain about 0.10 mg/L iron, and use a MultiTest: Iron kit to check levels, testing within 30 minutes due to rapid utilization.

How does this fit with the rest of the Flourish line? Flourish Iron is the targeted iron supplement in Seachem's coordinated planted-tank system, used alongside Flourish Excel for carbon, the comprehensive Flourish supplement, and NPK and trace dosing.