Green Snails?

I guess I can pluck some of these guys from the tank and raise them in a tank of their own to see if I can get it to change with a different diet or something. Just going to cross my fingers that it's nothing serious. I'm also going to be pulling the spixis just in case.
 
I doubt it's anything. I occasionally see the odd-colored ones in mine as well.
 
Just looks translucent to me. It's the same as the blue mystery snails looking that bright sky blue; They're not sky blue, and neither are their shells, but hey, combine flesh with shell and presto, sky blue. What you've got is dark snail flesh + light translucent snail shell = greeny colour.
 
doesn't look abnormal or anythin
 
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