HELP!!!!!! I was recently given 3 glass carboys. 2 -6 gal and 1-5 gal. There is residue on the insides that I can't seem to get out. I soaked in hot bleach water and brushed out what I could with a bottle brush. Then I tried the peroxide,baking soda, and water route with a cup of rice and sloshed that around but there is still some residue on the bottom and up around the necks. Any solution to getting this stuff out of there I don't want it to contaminate my beer when I rack it. Anything will help