Advanced Nutrients Grow,Micro and Bloom can be combined to provide specialized nutrients for plants in structura,foliar and blooming stages. Formulas can be custom mixed for specific applications by combining the 3 components to suit the needs of your plants particular growth phase. For best results: monitor nutrient quanity with a PPM meter and control nutrient strength. Replace nutrient every week. Remember! ALWAYS add Micro to your reservoir first, then Bloom and Grow.