Mammoth Silica 1000mlMAMMOTH SI was uniquely formulated to provide you a single formula and application rate to use throughout your entire growth cycle. Our unique formulation allows for increased bioavailability of silicic acid to maximize plant silicon uptake. Label rate: . 5ml per gallon City Line Recommends: Use as a supplement with any organic or hydroponic line. 1 ml L yields 50ppm Silicon (13ppm gallon.) May also apply to leaves as a foliar at a rate of 30 40ppm.