Brown worm in tank! ID?

[Armoredspider]

There is a small, centimeter long, brown worm in my tank! I was doing a water change after adding in a breeders net for my baby fish when I saw a small worm in between the net and the glass and one in the net! They are thick but short worms only visible by watching them move because at first the look like fish waste. Has anyone seen these before? It is too small to take a good picture of but I'll try to get a pic.