No matter what the motive, it’s never a good idea to turn a pet loose in the wild. Taking that one step can result in a kettle of fish — that’s goldfish in this case.

The ultimate size of a goldfish is limited by its environment. So in open water, with the right temperature and plenty of food, a 2-inch tank fish can easily quadruple in size — like the 5-pound goldfish caught from a lake in England or the foot-and-a-half-long goliath netted in Lake Tahoe. And one fish quickly becomes many until there are thousands, like the feral goldfish crowding a lake in Colorado.

Once Goldie becomes a mega-fish, he simply out-eats his native cousins. What’s more, goldfish waste stimulates algae growth, wreaking even more havoc on the ecosystem.

So don’t do anything fishy. Instead, make it your job to protect nature’s status quo.