Watching fish swim and bubble in a pond is so calming. They float effortlessly through the water, doing fish things, living their best fish lives. That is, until the Maine Department of Inland Fisheries and Wildlife busts onto the scene and douses your backyard pond with chemicals to rid the waters of your goldfish.

If you bring your pet goldfish outside to your backyard pond or aquarium in the warmer months, then you're breaking Maine state law. You could face up to $10,000 in fines for releasing a non-native species into Maine waters.

According to the Maine Department of Inland Fisheries and Wildlife, goldfish are tough fish who can quickly colonize and outnumber native species. They can carry diseases that threaten native trout and salmon.

Outside goldfish ponds are illegal in the State of Maine. This applies to any outdoor pond; as small as an aquarium or landscaping pond to as large as a man-made trout pond.

- Maine Department of Inland Fisheries and Wildlife

Even a small outdoor aquarium is illegal in the State of Maine. Sure, they look pretty, but you're breaking the law.

If the Department of Inland Fisheries and Wildlife is tipped off to your outdoor goldfish habitat, they will take measures to rid the water of your fish. According to an article from Bangor Daily News, a chemical called rotenone is sprayed into the water. "Rotenone, which is derived from plant roots, basically inhibits the oxygen and suffocates the fish," the article explains.

If you have goldfish in Maine, you'd better keep those things inside or face a penalty.