1wt per gallon is a minimum. Pumps should always be running 24/7. Keeping your water oxygenated is a constant battle, and will become harder once you have microbes in there. Proper res conditions should be your first line of defense against disease, and that means never letting the water go anaerobic.
Remember proper res conditions are:
1wt per gallon air pump
multiple air stones
water temps 68-75
Zero light leaks
Zero organic material
Adding the tea to your cuttings will help greatly. It takes a long time for the mycorrhizal fungi to form their network, and the more advanced it is the harder it will be to penetrate, and the longer it will persist once you start using nutes with higher P. So the sooner you start the better. Don't pour the water on cold if your roots are used to room temp. Warm it up by adding some room temp water, a 50/50 dilution is fine for cuttings.