Any aeroponics set up I have read about runs 24/7 but at intervals. Pump goes on 3 times a minute or so for a quick mist.

You can run less, but the main problem you run into is the root drying out. Not only does it stop getting nutrients, but dry roots no longer pull the same amount of air. Aeropnics, like bubblers, is a way for the roots to be amazingly oxygenated to increase overall plant size.

Just pay attention to your pump health and keep a record of how long it lasts. Like anything it will break down, but it you are running clean solution and have good misters the pump should last a while. Also make sure to clean the entire system with sledgehammer to another brand of flush to keep that salt from building up.

I have 3 aero set ups right now and run the pumps 24/7 on 2 of them. The third is on a timer.