Is this snail bad?


New member
So I have had my nano up and running since December '08, with few to zero real major issues... and just recently I found a BUNCH of these little snails.... they started out in the back portion where my skimmer is running and then just the other morning before any lights (or ambient light) hit the tank, I snuck up and found these little guys all over the glass.... I am hoping that it is not a negative infestation... can anyone confirm that these are good? or are they bad? THANKS!