Seachem Flourish Potassium. Seachem Flourish Potassium 100ml. Seachem Flourish Potassium 250ml. Seachem Flourish Potassium 500ml. Seachem Flourish Potassium 4L. Use 1 capful (5 mL) for every 125 L (30 US gallons).
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