Thanks Texan, it is truly appreciated. (please stop by my grow journal and say HI... and I give REP to anyone who says hey)
First, I would say that the NET POTS should not be directly touching the water. You should have a GAP between the bottom of the net pot and the water. There is no need to submerge them... Trust me, once the roots hit the water, they will GROW!
I'm not exactly sure what you mean by 'can I use the lid without the plants sucking to much water out'...
I will say... YOU WANT THEM TO DRINK... AND DRINK... The trick is to get them to drink while you have a decent amount of nutes in there... That's when you know things are working.
So, say you have a 10 gallon res... you would put about 6 gallons in there... or so... it's not rocket science, and the trick is to not do too much at one time. Little by little.
The light is probably the most important thing too... CFL's in my opinion suck. They are decent for VEG'ing... (the first 4 weeks or so) but you won't get NUGS... and that's what you want. I would do 4 plants if you are sticking to one tub.
Email me more questions if you like, I'll do my best to answer.