Be sure to ONLY use Schedule 40 or Schedule 80 fittings. They are designed to handle the pressure. Standard drain fittings aren't appropriate. Be sure to use lots of teflon tape on threads. If you can, get the 3/4" tape.

But be sure to check that the threads coming out of the top of the pump aren't stripped. They probably aren't. If the fitting isn't damaged, just using the teflon tape may be enough.