Grotek� Pro-Silicate��is a potassium silicate solution which can provide potassium as an essential plant element. Potassium is an essential element to forming plant structure. This product can also provide a means of elevated pH with its alkalinity. It is best to add this product prior to adding nutrients in your reservoir, or, pre-dilute it prior to application if it will be mixed in after nutrients. Grotek� Pro-Silicate� can also be used to modify the pH in a foliar spray.