Possible Parasite?

[Deteriminati0nn]

Hey everyone I was not sure where to post this since it is not directly harming any of my fish. But I found this little worm swimming around in my fishless, planted 20 gallon today. Can anyone identify what it is, and tell me if it could harm my fish in the future.

 

[rlederer]

Looks to me like a planarian. Planaria are free-living flatworms, not parasites, harmless to fish except perhaps very small fry.