How important is ph ?

ph is a lot, in veg you really dont see it, when your in flower and your ph was off during veg you will get low yields, the plant does not do what it should to at 100%, now imagine if your ph was off the whole grow, you would get maybe 45% less of a harvest from the plant, when you dial in ph from the start you avoid problems like deficiencies , ph also helps the uptake of the nutrients in to the plant cells that the plant needs, now you get low ph you get all kinds of funky stuff happing. with tap water you want to let it sit for 24hrs to get rid of the chlorine that they put in the water, tapwater is sometimes real high like 8 or higher, you can use lemon juice to lower that, you can also pick up ph up and down, or you can use nutrients that are ph- balanced , imagine that you are on a diet of good stuff how do you think your body will react? now imagine you are on a poor diet of nothing but sweets and junk food, almost the same with ph