In the homebrewing hobby there's the acronym RDWHAHB which means "Relax, Don't Worry, Have A Homebrew." It's used to reassure that a homebrewer's mistakes aren't that big of a deal or that something they're worrying about possibly messing up won't likely matter. Plus whenever it's seen, even by people it wasn't specifically meant for, it helps serve as an amusing and fun reminder that homebrewing is a pretty forgiving hobby and to enjoy it.
Is there a similar acronym or phrase for fishkeeping? If there isn't already a well known phrase, what would you propose?