Servus Mate✌️,
because there are a lot of mobile Nutrients, it makes perfect sense to have the water pH'd. You wanna get your pot emptied. I also add some enzymes to break up the rest of the usable bio material for the plant. Personally I'm not a big fan of flushing. Don't get why I should stress her so massively to the end. Keep going, your ladies look brilliant.
Servus, Oim.