SuperThrive and FF are both good at the same time. Super Thrive/ST is an addative that you should use with your main nutes. Don't use ST in flower because it can fluf out your buds and make them airy. FF products are good, with the super thrive, only use about a 1/2ML per gallon unless you are transplanting or the plants have experienced some stressthen use 1 to 2 ML per gallon.
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