If the bottom of my net pots are in the nutrient solution is that bad ? Can the plants still live this way, or does there need to be air space between the bottom of the net pot and the solution ?
you'll be fine. as your roots grow, you can get away with letting the water level get a bit lower without any harm. mine are drinking around 2 gallons a day in a 5 gallon bucket, if that makes you feel better.