brewtime

Recipes 

For the life of me can't get this black stuff off the neck of the carboy. I have soaked it with PBW and most recently with Oxyclean. Nothing I do gets rid of it. Anyone have any ideas or am I a proud owner of a new coin jar.

passedpawn

Recipes 

It's probably lead or some soft metal from the arm of a carboy cleaner brush. I wouldn't worry about it. You would probably need to physically rub it off.

__________________
Mornie utulie,
Believe and you will find your way.
Mornie alantie,
A promise lives within you now....

TRG

Recipes 

To me it looks like the glass was scarred/scratched... If a concentrated overnight soak of hot oxyclean doesn't remove it - I'd be surprised if it is a deposit at all. My bet is damaged glass. I wouldn't worry about it too much until it starts affecting your beer!

brewingmeister

Recipes 

I agree with the carboy brush. The handle is rubbing the neck and leaving marks/metal deposits. It's totally ruined unless you have a finger to clean it off.

__________________
............Alright Brain, you don't like me, and I don't like you. But lets just do this, and I can get back to killing you with beer......~Homer