Rays
A Wahoo fish
halibut
One fish I could think of is the Parrot fish.
The electric eel is a type of sea fish that can deliver a powerful electric shock to defend itself or stun prey. Its ability to generate electrical currents comes from specialized cells in its body called electrocytes. The shock of an electric eel can be strong enough to deter predators or even incapacitate small fish.
The fish you are referring to is likely a "sole." Soles are large, flat fish with a distinctive body shape and are commonly found in both freshwater and saltwater environments.
It is four letters in the word fish
Flush it
There are 4 distinguishable letters in the word fish, so there is 4! or 24 different ways can you arrange the letters in the word fish.
eel fish gives current
A fish which happens to be particularly large.
It's tuna. I know I didn't know they were in the ocean but, I looked it up.
You get fish letters from pressing (on a computer not a laptop) alt 4 2 6 one after another.