Brightwell Aquatics Potassion - Concentrated Potassium Solution for Marine Aquaria 500ml / 17oz Highly-concentrated ionic potassium solution Provides potassium, an important component of aragonite (the mineral secreted as skeletal material b 80,000 ppm K; considerably stronger and more economical than competing potassium products May be used to combat potassium depletion that often accompanies the use of zeolite-based filtration Formulated by a marine scientist.