How long do nerite snail eggs take to hatch? Do I need to do anything special in order for them to hatch? What do I need to do once they hatch? Will they be ok if left in the tank? Right now, all that's in there (29 gal.) is 3 swordtails, 2 platies, 4 corys, and 3 snails. I will be adding some baby guppies from my nursery tank in about a week.