While goldfish may seem like a harmless pet, things can take a turn for the worst when owners -- who want to dispose of them in a friendly way -- set them free in a local lake, pond, or other waterway. Experts say this method can actually wreak more havoc. "They grow bigger than you think and contribute to poor water quality by mucking up the bottom sediments and uprooting plants."  Although officials didn't offer another option for ditching the goldfish, they warn "pet owners should never release their aquatic organisms into the wild."