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SEACHEM Flourish Potassium 500ml


Seachem Flourish Potassium 500ml

Seachem Flourish Potassium is a liquid supplement that helps aquarium plants to thrive and grow vigorously with green leaves, stronger and firmer stems, without triggering algae growth.

Potassium helps to maintain vigorous growth of plants in planted tanks. The fact is Potassium depletes quickly in a tank with growing plants, or when the source water has a low mineral content.

In these cases, potassium could become the limiting factor to growth. With Seachem Flourish Potassium, you can easily supplement the potassium content in aquarium system, to prevent problems such as yellowing in older leaves, and ensure that your plants maintain their rigorous growth.

Flourish Potassium contains 50,000 mg/L of potassium, and is suitable for the natural planted aquarium.

Benefits of Seachem Flourish Potassium

  • Prevents yellowing of leaves
  • Helps plants to maintain rigorous growth
  • Ensures plant stems are firm and sustains a longer growth
  • Triggers plants to grow, but not algae

Potassium Dosing - What to Avoid

The most easily obtained sources of potassium are potassium nitrate and potassium phosphate. Both of these sources add to either nitrogen or phosphorus as well as potassium, making it virtually impossible to target a specific NPK ratio.

Seachem Flourish Potassium is derived from potassium sulfate, allowing the user to adjust potassium levels without affecting nitrogen or phosphorus.

Furthermore, Seachem Flourish Potassium will not trigger algae grow. It would only cause aquatic plants to flourish.

Benefits of Seachem Flourish Potassium

  • Safe concentration (4,500 mg/L phosphate)
  • Nitrate free
  • Safe for invertebrates such as shrimp
  • Enhances and accelerates the growth of aquatic plants
  • Does not trigger algae growth


Use 1 capful (5 mL) for every 125 L (30 US gallons). This dose raises potassium by 2 mg/L. Repeat 2–3 times per week or as needed in response to signs of potassium deficiency in older leaves which include: chlorosis (yellowing), necrosis (death/browning), pinholes in leaves, and weak stems and roots.


Amounts per 1 g: Soluble Potash (K2O) 5%

Derived from: Potassium sulfate

Elemental potassium is present at a concentration of 50,000 ppm (e.g 5%). Fertilizer laws require us to list potassium in terms of equivalence to a material that is not present (K2O) rather than the more scientifically sound method of simple elemental equivalence.