Bulkhead returns sizing

[Rohaus]

I bought some CPR bulkheads that are 3/4 inch. These will be my returns at the top of my acrylic tank. I have two holes at the top of the tank that are 1 inch and a half in diameter. I size them based on the recommendation from Amazon. However, when I put the bulkheads in I noticed that they don't fit anywhere near snug they're rather loose inside the holes. Now the flange and tightening it down is fine but I'm just curious if there is any thoughts on just how tight of a fit the bulkhead should be in terms of when you put it through the hole how loose should it be when you move it back and forth before tightening it down?

Again based on the recommendations that I've read online how about a one and a half inch hole in the sizing for a bulkhead, the recommendation was a 3/4 inch bulkhead for a 1 and 1/2 inch hole.

Would anyone recommend a bulkhead that might fit better into a one and a half inch hole? I'm just not sure if I'm comfortable with the space around the bulkhead and the hole.

 

[Rohaus]

https://photos.app.goo.gl/R2PAmXG4c3s3s3Dj8

 

[Rohaus]

 

[deeda]

Much better with the video!! I don't see an issue for a couple reasons: one - it's on top of the tank lid and two- the gasket and nut underneath will seal it from moisture from below the lid.

There is a graph on the forum somewhere that gives a general guideline on bulkhead fitting sizes and required hole sizes, it might be in the DIY section.

The question might be is IF the 3/4" BH fitting meets your needs for the return plumbing.

Here's the link to the chart Bulkhead chart

 

[Rohaus]

D deeda thank you!

 

[deeda]

You are welcome, Michael!