Hi Kronz,

Your pictures are a bit dark, but it looks like you have two airstones per bucket. I'd recommend four per bucket. Also, GOOD air pumps are a must! Like dejayou30 said, no Walmart junk. Go to an aquarium store and get some good dual output pumps, two per bucket. (That's one dual output pump running two airstones, so one airstone per output.) I like two dual pumps better than one quad because if one fails, you'll have some time to realize it before your plants' roots suffocate.

As for nutes, follow the directions on the label, only start at HALF strength and you can work up from there. A PPM/pH meter will be invaluable for this, so if you don't already have one, get one, period.

Yes, change your water once a week. You may be OK with tap water, or you may not be. The more chlorine in your tap water, the less likely it will work for you, but that's not the only nasty chemical they put in tap water, either. You'll find out pretty fast (a few days) if your tap water is suitable. If your temps are ok (65-75 F) and your pH and PPM are OK and you get root rot anyway (a slimy film that collects on the roots) then your water is bad.

DWC is really easy once you get the hang of it, like riding a bike. It seems really overwhelming at first, but once you catch on it's a breeze.