I have pre amended soil I only used this stuff in flowering it seems like megacrop can be used throughout.It is only a bloom booster, there almost no N in there so it’s no good for veg phase. It’s just boosting P and K. I haven’t looked in to the product, but it isn’t likely to have any Ca,Mg or any of the other trace elements you need throughout a grow. You need to get a “grow” nutrient and some calmag as a minimum. You start adding the bloom nutrient once flowering starts as the plants need for P and K increases.