tropical snail shell problem

[sanga]

Hi, I have a tropical tank for about 10months now.. I have 3 large snails.
I have notice they have ben getting a bit of green alge on them..
and now I'm noticing their shells are getting weak. they look like they arr getting eaten and becoming thinner in places.

any hints on what this is or how to stop it..

[Northernguy]

Welcome to the Fabulous AC!
Snails need a calcium intake to keep their shells hard.
What is your ph and water hardness like?

[sanga]

Thank you for the reply...

Not sure what they are, but will take a sample to the local Aquarium and get it all checked.. and see what they have to help the little guys out..