It seems as though many people think if the plant is sick that we need to feed it. There's a difference between a hungry plant and a sick plant. This is a sick plant.
The plant isn't even budding yet and is pretty small, it's too early for it to be starved of anything. The tips look like they were overheated or underwatered at some point, and the brown spotting on the fan leaves suggests that it's been dosed with too much of something. A 20-30-20 is fairly strong, so you can't give it too much. A couple small doses will carry it through most of the veg and bud cycle. I think your soil is possibly leaning towards the alkali side, which is not typical when you have spotting from nute burn, normally you would have acidic conditions, which isn't good either, just makes diagnosing the problem trickier.