that was filmed not to far from where i live and i have over 40 years of diving in such water. it looks just like my diving and much of my diving was in "oyster bay". the large bay is still home to oyster farms but you see very few wild oysters although they are coming back with the cleaner water.
mussels and barnacles like these are not really sub marine animals like oysters which can stay submerged.
they are intertidal animals and spend part of the time above the water at low tide. you don't find to many of them below the low tide mark.
clams stay underwater or just over the low tide mark in the mud where it is very wet.
you really can't keep northern shellfish in a tank very long because where they live there is so much fine mud and sediment that you can never feed them enough.
the water here where those creatures live has a visibility of usually 18". or half a meter for you brits
..hard to make capitals yet..
that avitar crab i use is a local hermit crab. i took that picture from a few inches away which is the only way you would see it