The answer would be YES……given a wide enough pot with a low enough flow. We have a brand new display area at Nelson Water Gardens showing how this can be accomplished. We have a large wide pot set over a disappearing reservoir. It may be hard to see in the picture, but there is actually water flowing over the top edge of the pot down the sides and into the reservoir below. The key is to have the pump tuned down so that you get the maximum flow out of the pot with the minimum turbulence.
Remember, your waterlily prefers calmer waters, so it is somewhat of a balancing act here. We also have a couple of goldfish in this pot along with a few submerged grasses (cabomba) to help keep the water clean and healthy for the fish.
This is somewhat of an experiment so come out to visit and see how it’s working! So far so good!