Hi there, so i was doing a sort of experiment with some water lettuce and after picking up all id done, in one of the cups it was fullllll of these little worms! They just wiggle around they don't seem like they cause any harm but I have no idea what they are, if they are dangerous, parasitic. Please help. I once found 2 of them in my 55 gallon and just discarded them. Please help me find out i couldn't find anything on google.