Nutes for hydro grow purchased...recommended feeding?

Hey all closer to embarking on my first grow :D just got a great deal on some nutes down at a local supermarket. Got some Miracle Grow all purpose soluble plant food for a hydro grow. Its NPK is at 24-8-16. it recommends the dosage of- outdoor plants 15ml and indoor plants 1.25ml. Now i know with nutes especially miracle grow to REALLY water this stuff down but if i was replacing the nutes in a DWC hydro box about 4Ltrs every 2 weeks how much nute solution would i need? I will be growing either lowryders,devilmatic or dwarf pineapple express in a PC grow box.

Thanks In Advance

GH