Arvind

You don't want it leaking of course, but is this going internally or externally to your sump?

Clean up the area as best you can, inside and out. #4 and #16 both will work well. You can even use Oatey's PVC cement, the kind in the can with the red label available at Home Depot. It won't be as clean as #16, but it will bond the two types of material.

You don't want to over do the glue job, as the acrylic will crack like crazy. Matter of fact, it is called 'crazing' when you observe tons of micro cracks. Just apply enough to to the job, as you want to mend it - what you don't want to do is apply it like caulk.

Applying it like caulk was what I had in my mind! Thanks Marc for this advice . I will try to apply as thinly as possible. In fact, now I am thinking I will apply one coat of weld-on, let it dry, then do a water test and if it sill leaks then will do it again.

I am going to order a #16 online. I am planning to put the skimmer externally for sometime. I am k ind of nervous that this seal may pop up again some day. But dont know what to do. Placing it in the sump is not an option right now since I have to make few changes in the setup to make that happen.

That's a good plan. If you seal it the first time, all is well. If you need to touch up a spot, that's next. Using too much can crater the material as it melts and collapses down (Weld-on #16 shrinks by one third, leaving giant air bubbles in its wake).

Maybe you can place the skimmer in a tray that helps direct any leaks by way of a bulkhead and some plumbing into the sump. A drip tray with a drain line / gutter.

Maybe you can place the skimmer in a tray that helps direct any leaks by way of a bulkhead and some plumbing into the sump. A drip tray with a drain line / gutter.

Thats a great idea! A fail-safe option. I can certainly work that into this setup. thanks for suggesting.