Hey Night... thanks for coming and the compliments. I really try to teach what I know. I learn a lot myself each grow.
Specifics about soil I cannot give, but I can def speak to those waterfarms. They rule dude. You can make your own but if you got a kit that's cool. GH makes them and they are a solid company.
I've never used GH nutes but heard they are good. Ratios are tough because I'm not sure what is the optimal one for MJ. Canna is 5-3-8 in veg... which is the same as 2.5-1.5-4 (to compare better with the Floragrow). Who's to say who's is better? I don't get hung up too much on that b/c there's sooo many other elements to optimize.
The only worrisome thing is the florabloom appears to have no N in it at all! I would def run the floragrow until you have fully sexed your plants (10 days-2 weeks into flower). They need N for that stretch. Does the flora micro go with the florabloom?
I recc PH buffered nutes. Except when your nute strength is really low (like seedlings) you won't have to adjust the ph at all.
I would also recommend some Superthrive (and only use 1 drop per freakin' gallon like it says!), and NOT being tempted by a lot of crap online or at the hydro store. Those dudes will sell you ANYTHING (for my experience for the most part).
If those GH do not have minerals including trace, start the mineral matrix 1-3 drops gallon after 2 weeks. Plants need 13 to grow and they need 'em all.
Make sure you toss those weak airstones that came with the WF (unless they've changed) and put in some nice monsters (Six inches or longer will keep the ladies happy -- at least in the plant world LOL). You will probably burn out the pump with a longer stone so you will probably have to get a new one. I recommend going to somewhere like
www.marinedepot.com
and looking through their airpumps. I have a pic of mine on one of these threads. Get a sturdy four outlet one for 50-70 bucks and you won't regret it. You do not want mature roots sitting in the bottom of a WF with a burnt out pump at 11pm.
Remember you are going to have problems just like all of us have had them. Plants are like people. Their probs don't always present like the textbook says they should. But you can build a solid knowledge base to guide your decision.
RE: Unknown problem. I don't want to engage in wishful thinking but it seems already the leaves are coming back.
I'll wait a few days. Changes and plant health are like a big boat... it's not going to turn around on a dime and will probably go forward a ways before making the turn (for hydro think TugBoat, soil think Ocean Liner LOL)