Snails are Breeding... but...

[Kronk]

I have some snails breeding like crazy in my tank and its been going on for a few months as the first batch have grown to 1/4" shells. Its cool but i am concerned they are all welks. I have tons of pods in the tank so if they are welks will they devour the pods in time? the eggs are like grains of sand in clear shells when they are big enough they crawl out. I posted a pic of the adult laying the eggs. I have seen them eating film algae on the glass I think so I am not sure if that eliminates them as welks....

Can anyone ID these snails?

Thanks,
Ken