hey guys just got a quick question

im about to add some fertilizer 20-5-5 so what i dont understand is how the PPM works and how to change it throughout the growth thanks.

use a &b formulas. there is one for vegetative state, and flowering state. use those and you will have awsome results. i full a large water bottle of a & b formula (cap full each) and flush it once a week. but i have used a 20-20-20 fertilizer and i just fill a shot glass add some water and mix until it looks like kool-aid and then pour it in the soil, then water it with clean water