you say a screw? how do u insert? u mean to the aerogrow water pump?For an airstone you may want to use a screw instead. You can adjust the airflow by turning the screw,be sure to use stainless steel.It will help keep water cleaner also. I read it on here tried it and it works. The plants needs oxygen to thrive what we pump in is not the oxygen the plant needs. It's the bubbles busting that we get the oxygen from,so any way you can make those bubbles it'll work. Hope that helps took me a lot of reading to find it somebody smarter than me figured it out. GG&HY To Ya !!
Add a 60 watt man or even a 100 watt cfl. And sit back and watch her grow man.