Leaking flange on gray tank

[vantage32fls]

I discovered a crack in flange in the gray water tank where it connects to the tank. It looks like it may be glued in with some sort of adhesive / sealant. I was thinking that I could use some 3M 5200 to seal it back up. Any other ideas or suggestions is appreciated.
Thanks Tom

[chuckster57]

Waste tanks are made of ABS plastic. We have had some luck using ABS glue to "melt" the parts back together. It may take a few coats of glue.

[mfifield01]

I used a specialty tape to fix the hole in my gray tank. Here's the link:https://www.amazon.com/gp/product/B00HJ6YEQ4/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

[vantage32fls]

The glue is what's cracked about 2in from bottom up. I took a picture but can't figure it out to post

[vantage32fls]

Thanks guys for the information, I built up around the flange with multiple coats of glue let it set up overnight and put on the insta holding tank patch today. Filled tank up with no leaks yet. Hope this works for a permanent fix. Looks like removing this tank would be a real pain.