60 gallon crock question follow up?

Hi, I’m the guy who had Stacey talk to you about my 60-gal crock. well, its on e-bay now and there are lots of people with questions about the dark color near the bottom. I would like to ghive them a good answer what it is but I need help. Please call me Tom 612-597-4194 THANKS!

question from: tom@siweklumber.com