Welcome to PB, you have come to the right place!

I don't have decorative fountains in my pond, but it would seem that fountains do not add a lot of aeration when compared to the bottom diffuser type of aeration. I suspect that you can run the decorative fountains as little as you like so long as the suction is not coming from the bottom of the pond (which would be rare). That could be a whole different animal.

Someone with fountain experience should be along soon to more confidently advise, I'm sure.

Congrats on the cool opportunity!


Fish on!,
Noel