Leaking sump return pipe

[Pvtgloss]

I just bought a used red sea max E 170 with a shoppe nano sump upgrade. I was cleaning it up and I filled the back sump a little to see if the bulk heads were leaking and found that the return pipe leaks. I've searched the forums but this seems like a problem you guys would have to see to be able identify the source of the leak. I'm not sure if it's the bulk head, o-ring, or hopefully not the glass cracked. Any advice would be greatly appreciated.

 

[Dburr1014]

Probably need a new seal on the bulkhead.
I don't see any cracks in the glass.
What oring are you talking about? Is there a face seal oring?

 

[Pvtgloss]

Probably need a new seal on the bulkhead.
I don't see any cracks in the glass.
What oring are you talking about? Is there a face seal oring?

There's a black o-ring above the threads in the second pic. That's the only o ring I found so I don't know if that's the only o-ring that should be there and needs replacing or if there is one missing. But when I look up the red sea o-ring replacement set the O-rings are in the color of red. I ordered them hoping that one of them will fit over the threads

 

[Dburr1014]

I recommend putting dow DC 111 on the orings for added sealing.

 

[Pvtgloss]

Sweet. thank you.