Just found a sundial snail in my tank

Just checking out the tank as I got home from work and I see this odd snail on some zoas. Sure enough a dang sundial snail. 1st one I've ever found in my tank. I grabbed him up and chucked him in the woods, that little zoa eating jerk.

I see they're nocturnal so I'll need to schedule some midnight wake up calls to check for more.

Anybody with have some experience with these guys? Does one necessarily mean many?

Thanks

Oh and here's a pic of it hanging out with some of my pocket change.

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