I would think they'd be a bit bigger in a 5gal pot don't stress tho, you always run into problems your first grow
Read this
http://www.sky.org/data/grow/
Don't buy into snake oils learn to read your plants and what makes them tick:weed:
I've never ph'd any of my water when I grow in soil and I'm yet to have an issue CUZ of it.
Reason I told you to repot is because you mentioned the plant is a month old so I'm assuming it's been in the same pot for a month. Your nutes ran out in that soil, or the root system has out grown your...
Without "chems" aka salts. Your plant wouldn't grow, honestly flushing is pointless IMO you mentioned you are in the final week so I take it you'll harvest soon?
Dude you're growing in soil. That acts like a really good buffer you mainly pay more attention to ph in hydro or soil less grows.
If the plant is a month old, have you up potted? Maybe you need to add nutes now
I begin to lst when my plants have about 4-6 nodes then I'll top them 3-4 weeks after I've lst'd. You don't want to do both at the same time since it'll induce a bit too much stress IMO
Also if you want to see the sex of the plants you'll need to do 12/12 or you can veg for about 6-9 weeks and wait for the plant to show its sex based off maturity instead of photoperiod