If you feel more comfortable with 1/2, then do 1/2 but for sure you need to use 6 gallons on each pot for a total of 12 gallons. I know that sounds like a lot but they need to get flushed. If you don't want to buy distilled water, if your tap water is completely jacked up ph wise, then use tap water and boil it for 20 minutes. That would be long enough to get the chlorine out. Of course, let it cool down before you water them. 2 gallons will not be even close enough.
Well i was just gunna flush my AWW#1.. My AWW#2 seems to be doing ok..it may be overfed a bit but the leaves are still green and it looks like its where it should be... but the AWW#1 got even more pale/droopy over night so shes my focus for today. i found another gallon so right now i have 3 gallons of distilled water which i plan on putting 4 tablespoons of BB and 1/2 teaspoon of TB into each one. when i usually water her it doesnt even take a gallon to get 10% runoff..im kinda stressing though cause she needed water bad yesterday and i think its a must that shes fed when lights come on at 5:40 p.m but i just noticed i barely have any ph up at all left definatly not enough to ph 6 gallons maybe enough for my 3 gallons and i dont have anything here at home that would work i probaly cant get some until this weekend