flat fish
That's called the flatfish!
Better question: why are there evolutionary niches allowing flat fish to thrive? Three answers, although you shouldn't consider me an authority: 1. Flounders lay flat on the bottom, and flatness allows them to be less conspicuous. 2. Flatness minimizes shadows on the ocean floor, thus aiding in stealth. 3. In coral reefs, a flat body and a long nose allows fish to get at food inside coral heads. In each of these three scenarios, it's not hard to understand how flatter fish would be more successful -- and therefore more likely to reproduce.
You format the hard disk
Hard Coral is not a fish but, some small fish live in hard coral.
4 toes and one thumb behind it but it is very hard to see clearly.
yes,it is hard to clean out a pet fish's filter
flat and hard
yes it is hard
A hard blow with a flat object.
wash it HARD
If you hit the fish hard enough yes.
You buy it...