i recently tossed together my dwc bansai mother bucket... the growrocks and rockwool were constantly a bit too wet if the waterlevel was mantained beneath the netpot.. i only have about 1/4-1/2 a gallon of solution in a 1 gallon bucket.. so figure the water levels about 4"-5" below the pot.... once the roots get into the water, then it doesnt matter how low your water is, as long as it's not bone dry in the bucket.. try to keep the conents of the netpot as dry as possible when the roots are a danglin'..
