Have you recently added anything to your tank (plants)? Malaysian trumpets snails are quite proliferative. Fortunately they are easy to see against the white sand.
MTS are great for sifting through sand.
I would let them be at this point. You do want to be prepared to control population at some point.
What are they called? I’d like to do research
To me, it is a Malaysian Trumpet snail. If so, in limited numbers they are not a bad thing. Keeping them limited is hard
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I came home after a 10 hour shift and i see this. It wasn’t here before. I seen small ones before and removed them. Where did it come from?