First time Hydroponic grower, chemical question

well me and my cousin decided to startgrowing hydroponic he said he knows everything except the 3chemicals we need to dillute with the water can someone please explain what these 3 chemicals are and also how much of each should go into the water please and thank you, its greatly appreciated

If your cousin doesn't know about nutrients then he doesn't know anything about hydro. Read this: http://boards.cannabis.com/hydroponi...iscussion.html