6.5 is he absolute min. for eggs, but I don't honestly think you will get any at that size. Remember a male mates with the female no matter how big she is. But if she does become gravid, you will prob. only see 1 or 2 eggs about 2 weeks or so from now.
Please watch them to make sure that he is not aggravating her too much. A 1:1 ratio can be dangerous to the female. Bullying is easy to miss if you think she's shy or not hungry or not active. Things are okay until they're not. Things that seem to be working don't always keep working long term.