I like the idea so I'm giving the stars.
Poor execution though.
The acting was on point.
Kids were dumb as rocks. Especially the eldest daughter. Didn't she learn sh*t to not wear headphones because her mom almost died because of that?!
And the stupid brother did a lot of crying on their father's dead body. A while ago you said you were 13 and not a kid anymore.
They definitely went cheap with this because I didn't think that's how the sea floor would look like if the water receded.
Also, they were always showing the POV of the critters because they can't afford to CGI a swarming critters.