Here is an old Bill Cody post.

Walleye Spawning

He says oxygenated water is the most important thing for the eggs to hatch. That means either flowing water, or your most wind-swept shoreline.

Unfortunately, silt covering the eggs is also a means to deprive the eggs of oxygen. In my muddy base ponds, the most wind-swept shores are the ones that exhibit the most silt in suspense.

I do NOT recall a Pond Boss thread about placing walleye spawning beds near the moving water adjacent to aeration systems. I think that might be a way to significantly increase the eggs chances of survival.

Here is a link to some guidance specifically for walleye spawning.

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The rock size they recommend is 4-12" in diameter. They also recommend surrounding the bed with up to ten boulders. Finally, they even recommend installing some silt curtains.

The last part seems a bit confusing. Erecting silt curtains will also restrict the amount of water moving over the spawning bed.

If I really wanted to make optimal walleye beds in a small pond, I would position the bed adjacent to a diffuser bubbler at the point where the water in the created convection cell starts to move back downwards. I would then put silt barriers on the other three sides. I think that would work to actually enhance the diffuser convection cell. Deep, clean water would be coming up to the surface and becoming well-oxygenated. This should also create a slight elevation of the water surface. Instead of spreading out equally (like it would in an unconstricted environment) it should be restrained by the silt curtain and the "elevated water" should tend to create a convection cell back down to the diffuser.

P.S. The other interesting point in the Canada guidance was sneaking out at night with a spotlight to check the locations of walleye on their beds. They said those big googly walleye eyes will easily reflect the light and mark their positions.

I hope that helps a bit with your project. Good luck on your walleye recruitment plans!