surprised at lifespan

[tedmc2]

In Aug of 2004, I added 12 Nassarius Snails to my 75 gal with new live sand. Now, a year and a half later, I have counted up to 9 of these guys out at a single time.

Does anyone know the lifespan of some of the inverts, including Nassarius Snails, and how long have they lasted in other peoples tanks?

Thanks
Ted

[The steven liu]

Mine has been living there for over a year and no damages.

[bertoni]

Snails vary in their life expectancy. Some can last decades. I don't know what the range is for Nassarius, though.