I highly recommend a TDS meter along with the pH meter... you can pick one up on ebay for around $20... this will help you keep track of the nutrients your plant is/isn't using so you can make adjustments accordingly. As far as the multi-site tubs go, they're nice when you're running clones or a very uniform strain, but you'll find that each plant has different requirements when grown from seed and they'll all grow at different rates. This can make for an uneven canopy and can ultimately hurt your yield due to reduced light exposure (one plant towering over another). You should be fine with your auto flowering strain... those don't grow to be that large and they stay pretty uniform for the most part, you're just sacrificing quality for simplicity imho... Another thing that I haven't seen mentioned yet is resevoir temps... this is rather important although it is overlooked regularly. Ideally, you don't want your water going over 72 degrees, preferrably in the low to mid 60's. This strongly reduces the chance of certain bacteria growing in your resevoir and killing your plants. When I first made my tubs, my temperatures were in the high 70's- low 80's and I noticed a film developing on my lines as well as the inside of my container... I used Reflectix to insulate and lightproof my tubs and I have no more funk in my res while my temps stay around an ambient 70. I add a 22oz frozen water bottle once a day to my resevoir to bring the temps down to around 64. If you have any other questions, please feel free to ask. I run (3) dual site tubs perpetually at the moment, each tub holds 3 gallons of water and has (2) 5" air disks... but I'll definitely be moving to a 1 container/plant system as soon as this next run finishes.