Wise advice on this page. Wouldn't be smart to stock commons even in a private pond, because they really will take it over, and if it is not very big and deep, they turn the water all muddy. Hard to bowfish in a mud pit. Gars won't get very big in a small pond, because they'll eat up everything else and have nothing to feed on.

In a public water, it would be very illegal to stock either gar or common carp, or any fish. You are not allowed to go around releasing fish into public waters, and fines can be quite substantial.