Why does the water look so very different from the editor in UE5 compared to the final render?

When I created this scene I purposefully wanted a fairly calm water surface that is easily seen through. You can see in this image the left is the editor and you can see the pebbles beneath the water just fine , there are waves but they’re very subtle (When I Alt-P in the editor it looks as I intend it to). On the right is a render to png in 4K, the water is going crazy - really crazy.

Why does it look so very different?

looks like the refraction of the water + normal map is distorting it.