Flourish Tabs™ are growth stimulating tablets for plant roots. They contain essential trace elements, amino acids, and vitamins. They are rich in iron, manganese, magnesium, calcium, potassium, inositol, choline B₁₂, biotin, and other factors that have been determined to be beneficial to aquatic plant roots. View a chart of Flourish Tabs™ constituents and signs of their deficiency. They contain no phosphate or nitrate that would promote algae proliferation. Each pack of ten tablets treats a 12 X 30 inch plant bed twice.