Looks like you got everything you need already. I personally do CalMag at about half strength with no issues, measurements on the bottle are what I use. Personal preference on that I think (or plant preference). I've gotten away with not using it but I also use tap water. Manifolding techniques are easy, just make sure you have something to tie them down with or they'll stand right back up. Here's a couple examples for you from some I did last night. I used the quadlining technique this time but it gives you a general idea of what you may want it to look like. My space is a bit bigger so I'm sure you'll be scaling it down a bit. I'm also working on my big top fed rdwc setup so I can separate my hydro plants a little bit, was leaking a little last time I used it. Had an unfortunate mishap with my fan and it almost took 3 of my hydro plants out completely. Still salvageable, just need a little time to heal and they'll be good as new. Including pictures of all that too.