Hey mouse that looks like alot of good advice,, Im running H&G too so I will have to check out your thread for any ideas. One thing I'd like to add, is before you go crazy buying all these expensive bottles of whatever, get yourself a pH pen. It'll do alot more good than any other product you can buy, when your pH is out of whack your just waisting nutrients cause your plants can't absorbe them. If you have one of those drop test kits with the little glass vial and eye dropper thing all I can say is I am not colourblind and when I check a solution I thought i had put to pH5.8 with my drop kit, and tested it with a digital pH pen it turned out to be 6.3
So thats the best recommendation I can make for you.