Using The Go Box Now But Got Megacrop Coming In Tomorrow

should i use both at half strengths or choose one over the other maybe use megacrop and a little bit of anything xtra i might wanna add out of the go box? what do you guys think? anyone used both before? also megacrop has a promo going on for free 230 gram bags shipping is 3.18! i ordered 3 before i even got to use it lol just look at the ingredients its made for growing cannabis!