Lion Fish are an invasive species in the waters off of Florida that have no predators and out compete local fish.
Florida man Courtland Hunt modified his Glock 9x19mm handgun as part of a larger societal effort to curb the lion fish population, in a way most befitting a Florida man.
It features a special muzzle device designed to muffle the shock waves of a gun being fired underwater without being a suppressor to avoid legal barriers.
He attempted to start a business selling these 5 years ago but their website is password locked and says:
Site is in revision for upcoming product release 2022.
So the business is likely dead.
There’s not much reef below 100 meters, is there?
I don’t know about that, though recreational diving ends at about 30m for safety and pretty quickly after that you get into your specialty breathing gasses.