Unsure what the deal is with the synopsis here on IMDb, but it's all wrong. This film is about some killer fish call sargasm and shark and some others shown in bleached out red color and a creepy scientist voice over out of an ed wood movie who turn half into one of these.
Also IMDb says this was made in 1999 but it sure looks like late 60s or early 70s to me. In fact it appears quite a bit was filmed silent and dubbed with voice over like many cheapo films from the era.
So the mad scientist turns into an aquatic animal that looks like the elephant man! Then he goes on a rampage with a tiny spray bottle spraying other fish.
I swear, this reminds me completely of ed wood. Nothing makes sense at all. And the monster costume apparently didn't provide good vision cuz it keeps tripping!
It's filled with tons of stock footage of fish in aquariums. Unlike ed wood, however, this is not bad-good. It sort of wears on you. Can't recommend.