I added my goldfish to the pond in the dark, so I was using a flashlight. While I was shining it in the water to catch a glimpse of the new fish, I spotted a very strange creature. It looked like a miniature eel, but I figure it's a worm. It was black, thin, 1.5-2 inches long. And it could stretch out really long. It swam around near the walls of the pond and sometimes looked like it was slithering on them as well. Any ideas of what this is? I hope it will not prey on my baby goldfish.