8 weeks old clones ?
Pictures and more info would be nice, specially some info about if your in hydro or soil ?
And what do you mean with that question ? what Brand to use, what numbers or what strength ?
I had good experience with GH flora duo in the start using the Lucas Formula
http://lucasformula.com
And I was told good things about there flora Novo as well, both will do the job and is a easy way for a beginner no matter if you grow in Hydro or soil