Snail, slug, worm or something else?

[redpine42]

I've now seen two of these in my aquarium. It is very very small, maybe 1/64 of an inch and very hard to take a pic of at that size. It moves like a snail on the glass, was wondering if anyone has any idea.

BTW, I'm finding it fascinating the things that pop up in my aquarium. Thanks!

 

[cristata.reef]

Flatworm

 

[redpine42]

Flatworm

Thanks. Good or should I be picking these out?

 

[wowkingjames]

Pick them up not good.

 

[saltyfilmfolks]

https://www.lionfishlair.com/hitchhikers-guide/

 

[KJ]

Flatworm