Just buy two bulkeads that fit desired PVC pipe size along with correct hole saw bit and plumb them together, very simple to do. When ordering your bulkheads just ask what size fits your need.
It can also be done with regular PVC plumbing parts, don't know exact name of parts but they are threaded on one end and you glue the other. You need to make a rubber washer for the threaded end. If I'm at the hardware store this weekend I'll take pics of the parts for ya.
Make sure you connect close to the floor.
Sent from my iPhone using Tapatalk