Groupers are a family of large sea bass - very unrelated to Pompanos, which belong to the Jacks and Pompanos family, and even more unrelated to Piranha, which are much more closely related to carp. None of these look at all like a dolphin fish.

Or, are you saying there is something called a "Red Pompano" thats like a grouper? Haven't seen such a critter referenced anywhere. Fishbase lists 302,900 common namesfor fish, but no "Red Pompano".