water level must reach the bottom of your netpot barely touching, if they seem dry, you can help them with raisin then lowering water level often to keep rocks moist like a flood and drain until roots hit the water. oh and I think that you need significantly more air, it's not the same requirements like fish, you need at least 1 airstone for 2 plants IMO and if plants will grow big, you would need 1 fore each