I've Found a Stowaway!

Looks like a ramshorn to me and if it lays eggs you will have many more to come. If you don't want more snails from this one then put it down now.

Q
 
If you don't overfeed no snails will overrun a tank.

If you overfeed, any snails will overrun the tank.
 
I prefer MTS ( Malaysian Trumpter Snails) more than any other pest snail (ramshorn or pond snails).

But yuppers that looks like a ramshorn with its rounded shell.
 
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