Seachem Flourish Potassium provides concentrated potassium to support vigorous growth in aquariums with natural, living plants. This safe, effective supplement helps you avoid potassium depletion, yellowing leaves, and limited plant growth. Flourish Potassium contains 50,000 mg/L of potassium - one of the highest concentrations available. Water with low mineral content or systems with rapidly growing live plants can quickly deplete available potassium, causing potassium to become the limiting factor for further growth.