If it's just the shrimp in there I'd lower the temp to 72F.
Ghost shrimp are not hard to breed, they'll do it on their own and I frequently saw my females holding eggs. The problem is raising the young. Ghost shrimp give birth to larvae, and depending on the species these may or may not require brackish/seawater to develop properly. In addition to that, they require small food when they are born.
If you want more detailed info on raising them I would do a search in the Invert board.
To be absolutely honest, it's not worth it in my opinion to go through the hassle of raising them. They're dirt cheap and not hard to come by.