Black spot in fermenter

[MoonBrews]

I was running CIP on one of my fermenters. Inspecting it afterwards, I noticed a black spot on the cone, and it looks like it's along the glycol lines wrapped around it. I'm really hoping someone out there knows what it is and how to fix it. The picture isn't great but it's the best I could manage. You should be able to spot it by the little white outline that looks vaguely like a battleship. Thanks for any help.

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[J&B]

Looks like an unpolished weld, probably for the jacked. Had the same thing in one of our tank. Polished it down. I am not too good on metals but we had contact with a good stainless steel welder who gave us some kind of paste and I think it was to oxidize the are during pollishing. The problem as I can see is that there a risk for braking the oxidizing layer and in time have problems with micro fractures in the stainless below.

[MoonBrews]

Looks like an unpolished weld, probably for the jacked. Had the same thing in one of our tank. Polished it down. I am not too good on metals but we had contact with a good stainless steel welder who gave us some kind of paste and I think it was to oxidize the are during pollishing. The problem as I can see is that there a risk for braking the oxidizing layer and in time have problems with micro fractures in the stainless below.

So do you think this is something I could have a decent welder take care of? I know nothing about welding, but it's nice to hear that this may not be more serious than that.