Looks great Flump! That 70s porn star bush is really gonna get bushy now!
I've never topped like that, going down that far but will have to try sometime. I jut top the very top tiny growth. Many ways to skin this cat. I also like to FIM which stands for F*%× I Missed. Top but don't get the whole thing, get like 90%. A bunch of leaves will grow funky like you clipped the ends but it will get very bushy.
For brix, I don't think your using enough. I'd mix 1oz water with 1ml of brix. You may not use it all but you'll use most by the next time you do it, she'll be a monster. Then mix more as she gets bigger at the same ratio.
Cheers!