This is what I would do for nutes:

Go to a hydroponics store and get a good 2-part Nute, 1 for vegetive, and 1 for flowering. Also get another product that contains micro-nutrients to add to your flowering nute. These Products are expensive, but totally worth it. You can ask whats best at the store (just be careful how you do it), but I have heard nothing but good about General Hydroponic's Floranova line. You may have trouble finding brand's that people tell you to buy (I can't find General Hydroponics stuff anywhere in my city) , But stay away from MiracleGrow and Peter's and shit like that it's okay for tomato's, but it's a waste of time and money when growing Cannabis.