Got 5 nerite snails. I've posted in several forums, and searched the internet for info. What I gathered is as such:

1. about 80% or more of nerite are sea water. Most others are brackish water. Very few are fresh water.
2. The specific nerite that I've got got "horns" on its shell. For this, it will lay eggs in both fresh and brackish water. However, will only hatch in brackish water.
3. When hatch, the babies do not look like snail. No idea how it looks like!
4. The babies will swim to sea water, and than later come back to brackish, or fresh water!!!

See why I gave up breeding them?!

However, also heard that they are one of the BEST snails to clear the algea from your tank!!