yes a 600 would be good to use

and for more organic stuff look into humus, beneficial bacteria, guanos, seaweed products, compost, compost teas

somewhere around the bottom of the basic page or maby the next page there is a bunch of maximum yeild articles that are good read, then as stinky said faq, read some basic grow books or get a bible. good authors, greg green, jorge cervantes i here is good, bog, soma, and afew others are great reads