I have a gray water flexi tube leading from my house outside, which my
sump pump (and filter backwash) dumps into. Right now these two are in
a 2" PVC pipe that just stick into the open end of the flex tubing.

I want to install a 4" PVC drain pipe so that my shower, washer and
dishwasher also dump into it. I will need to join the two pipes (4"
PVC and 4" flexi pipe), just not sure how to do this. Please advise.

Thanks!

DeanB