I've heard that more nitrogen for vegging is best but I've also heard the best number for vegging is 20-20-20 I have both a 20-20-20 and a 30-10-10 and don't know witch one I should use.
You shouldn't use any of them, it sounds like chemicals. Nitrogen is needed more for veg and phosphorus for flowering. The plant needs all three during the growing process but in different ratios like I said earlier. Also dont forget about K which you can get from Mollasses, among other fertilizers. The plant also needs boron, iron, zinc, selenium, sulphur, calcium, magnesium, copper, nickel, and about 50 more trace elements, all things you DONT usually get with chemical fertilizer.
So what am I supposed to buy I've heard 20-20-20 is the way to grow! So I should use something different like what?
You could use both and see which works better. Use only 1/4th the recommended dose and use it gradually. It is very debatable as to which would work better.
You should use something thats not just a number. Like Earth Worm Castings or Alfalfa meal or cow manure or chicken or horse shit or blood meal or bone meal or compost from your bin or Roots Organic, FFOF Harvest Moon. Take your pick. Fish Hydrosylate is a good even 2-2-2 or 3-3-3 or whatever it is if your trying to get something like that. Or you could have everything mixed into your soil already but that takes a tad of experience.