I noticed the below pests in a tank that I used to use as a QT tank. Right now I have a lot of zoo's, mushrooms, and leathers growing in there to possibly frag. I went away on vacation and came back to a tank full of these guys. They are an off yellow with a red mouth and move rather slowly. I didn't notice any on the corals until tonight when I saw some moving rather fast on my green tipped leather. Are they flatworms?
I know the picture isn't the best but you can see the red mouth that I'm talking about. I will try to get another picture but I can't seem to find the better camera. Any help would be appreciated.