I would start in rockwool but you will be alright. We all must give it a try and see what works for you. Sounds good, you been reading that's a good start.

Remember no nutes for 2 weeks at least and then bring it up slow.

GH 3 part is good . I used the lucus formula. Don't forget the Cal-mag plus. It's a must for hydro no mater what nutes you use. Superthrive is good too, it's a B1 complex.