Quarantining fish is putting new tank mates in a seperate tank for 1-2 months to make sure they are healthy, eating, and no parasites. It is highly recommended, but I think we have all been giulty of not using a QT. I also think we have all had losses or issues from not using one. Also about the laying eggs who knows could be 2 months or never or anywhere in between. Usually about 1-2years of age.