Can someone tell me what these are and if they are harmful?

[MaverickReef]

I have quite a few of these over my glass bottom and in my rockwork. They are probably up to 1/4" in size and are hard to scrape off of the glass. Everything in my tank seems to be doing well, just not sure what they are and if I should do anything to remove them.

 

[MaverickReef]

I have quite a few of these over my glass bottom and in my rockwork. They are probably up to 1/4" in size and are hard to scrape off of the glass. Everything in my tank seems to be doing well, just not sure what they are and if I should do anything to remove them.

I think I have figured out that they are limpet snails and function mostly as clean up crew if they are the white/tan variety. Any additional information would be helpful, thank you!

 

[AydenLincoln]

Yes limpets! Good guys.

 

[MrGisonni]

Limpets

 

[Mr Fishface]

Yes looks like limpets. I assume like any CUC, they just need something to clean.

 

[flyingscampi]

I have a small self-perpetuating army of these little guys. I don't bother with normal snails anymore! The hermit also gets an occasional snack.