"Clean fish" is correct and usable in written English.
It is used to describe a fish that has been cleaned for consumption or processing. For example, "The local fishmonger sells fresh, clean fish."
Special sink to clean fish?
Young dandies haul coal, and ladies clean fish.
Clean fish tanks hold a modest selection of sea creatures.
Part of Wolfred's job was to catch and clean fish if Mackinnon asked.
"When I can, I clean fish at the market," he said.
Tobin's apartment is clean; fish swim in the aquarium; his new manuscript is a money-spinning adult book; he has taken responsibility for his life.
And one cleans fish outside.
A whole cleaned fish -- easily five pounds -- went for $3.
Cleaner fish are highly specialized fish that pick parasites off the skin of other fish.
Mr. Romney, named one of People magazine's "50 Beautiful People," has run on a common-man approach, staging "work days" in which he hauled garbage, drove a tractor, cleaned fish and slung sausages outside Fenway Park.
It's not Twitter's Cleaner fish, even if Twitter bought up the app and launched it into existence (unlike Instagram's organic growth that was later bought up by Facebook).
