Diy !! How to connect pvc to your pool !! pvc conduit reducer did the trick 

I think I got them at Home Depot. Some have little ears I cut off to make round . But some are round just hafto sand off the writing to make a smooth edge. Mine are still working fine . No problems. You can check all plumbing storage. Lowes , Home Depot, or Ace Hardware . They should have them

What are these fittings called

Box adapter 1 1/2 . With eletric conduit section