Your harvest will suffer if you persist with LED for the complete cycle, LED are very good in the veg phase however once you switch over to 12/12 LED do not have the intensity to produce large buds and weight will be greatly reduce in comparison to HPS .... go and get your dollars back and buy...
feed twice weekly, large spoon amount and heat the spoon before hand ... add to the products you already feeds your plants and apply till its time to flush