*Intertidal life- so we are talking about the same thing: http://www.montereyinstitute.org/noa…10/l10la2.html
I don’t think intertidal life had a problem surviving the flood.
The water column did not need to be several km’s deep to cover the early earth. We cannot assume that what we see today is what existed in the past. The pre-flood mountains were likely not as high as they are today. That’s why we find sea shells on mountain tops. These areas used to be the ocean floor and they have risen. The basins also were not as low as they are today either.
So the amount of water needed to cover the planet was probably not as much as you might think. Its all in our oceans now. We probably lost tons of species of life during the transition, but some survived. They may have capabilities that we don’t know about to survive flooding conditions or perhaps many can live much deeper if necessary.
There is no reason to assume that the flood event was a hellstorm event for the entire duration with with unlivable water conditions.
Life that was dependent upon intertidal-life type conditions were safe. I think all we are seeing here with “intertidal-life” are adapted, post flood creatures that were able to live in the new conditions. The water probably had a initial “intensity” to it as the fountains of the deep broke loose and the floodgates of the sky opened (Gen 7:11) but the remainder of the event might have been still/quiet for the most part.
The creatures that could survive in the new earth, post flood, are the ones you call intertidal-life. The old world that was is gone.
There were tides and shorelines pre-flood I bet, that’s why these creatures exist today.