All of my tanks are on an on-demand drip system (i.e. I turn on the water and it drips water to the tanks). And almost all of my tanks have PVC overflows. I'd add 2-3 for redundancy.
a pvc overflow or overflow box will work.
you have some options. pvc overflows without the clear tube on top. should be hooked up to an aqua lifter pump. as you will not be able to see air forming inside.
an overflow box usualy has a clear tube going over the aquariums edge. you may need to remove air from that tube from time to time. keep an eye on it.
theres also a pvc overflow design with a clear tube on top. you can see air accumulation with that design much like the overflow box.
I use this DIY overflow when rains overflow my sump.
The way it is designed, once primed, it is amazingly efficient, and stops and starts whenever water hits the right level.
Although the PVC on this is small bore, I have made larger versions, for heavier flow rates.