I have one more question. Should I add K2SO4, MgSO4∙7H2O and CaCl2∙2H20 to the topsoil for K, Mg and Ca? My tap water has a low GH, usually less than 2. Or, should I add Barr's GH booster? I plan on using the following dosing regimen: Want more accuracy? Want daily PMDD style EI dosing?