So i have a carboy that i didnt clean properly after a batch and it sat for about a year and a half like that. Now im trying to get it clean so i can use it again but im having a hard time getting rid of the brownish film near the top. I've soaked in oxyclean and hot water (for couple hours), twice and shook the heck out of it. Still there. I'm not able to get a brush to that spot.
The rest of the glass looks sparkling clean its just the one area. Any other suggestions?