Is there anywhere that i can go that explains which nutrients are needed for growing from start to finish?
I can tell you what has worked for me. I swear by General Hydroponics Flora Series three part liquid fertilizer. This fertilizer comes in grow, micro and bloom parts that come in seperate containers and you mix them to fit your need.
For the vegetative stage I use the formula that the manufacturer suggests. 3 parts grow, two parts micro and one part bloom.
For the Flowering phase I use the lucas formula. The lucas formula uses only the micro and bloom parts of the three part general hydroponics flora series.
The lucas formula is simple: 1 part micro & 2 parts bloom. 1300 ppm throughout the bloom cycle (1100 - 1400 is fine).
I am only on my second hydroponic crop and still figuring things out, but stumbled onto the lucas formula on my first crop, with stunning results.
I have a friend that is too impatient and switches fertilizers continually and he keeps screwing his crop up. He keeps buying these exotic supplements thinking they have some magical properties to them that will make his plants grow crystals, etc. I would stay away from stuff like that and keep it simple.
General hydroponics is professional and flexible. It is also relatively cheap.