Help With ID on Stringy White Mass

[marcell06]

Can someone help identify this for me please. It is soft and attached to my glass. Literally appeared overnight.

 

[blowmecius]

Sea hare egg sack

 

[marcell06]

blowmecius thank you for the reply. So the next question is do I just leave it alone or do I need to worry anything is going to hurt it?

 

[blowmecius]

Sea hares have been know to breed in captivity. If it were me, I would just leave them and see what happens, however even though sea hares are hermaphroditic, they are not self-fertilizing, so two slugs are required to breed. If you only have one, the eggs are infertile and will not hatch