Scuba Diver in Underwater Quicksand

[DrScaphandre]

Since I've been doing my Scuba Art Jam, I thought why not have some scuba quicksand? Cute divers underwater, and stumbling into some underwater quicksand. For example, a diver finds a treasure chest, and floats down and stands on the seafloor to get the treasure, but then starts sinking as it's actually quicksand.