A couple of months ago after a tank transfer/upgrade, And I added a group of Molly’s after acclimating to full salt water over a few days as an inexpensive group that I wouldn’t to have to quarantine. I think one of the females even came and pregnant they were babies in the tank within a week the first group of babies are about 3/4 of an inch and the second group of babies from this month are about a quarter inch.