i too use m.g.'s ferts...same npk ratio but mine's at 24-8-16 and i dilute it further to 1/3 of what directions call for. they get this after week 3 or 4, depending on their needs and then every 2 weeks until flowering. i use schultz' bloom or superbloom usually (at same rate as the veg ferts) but this year going to try 'pure blend pro bloom' on half and the usual on the other half. they only get 2, maybe 3 applications total during flowering...