Long period of time between waves/tides as Flood rises.
Be careful how many made-up, unscriptural waves you try to squeeze into a one-year flood. There are a lot of layers to explain.
Of course, that's an experiment that creationists could do: One tank with waves every few seconds, one tank with two tides per day, one tank with a wave every week, etc. It should be easy enough to figure out what conditions would preserve footprints. Why don't creationistsdo that?