Brown water and sludge above cabbage seal with stone.

[mawil1013]

I'm 68 yo and made my first fermentation, found a YouTube'r recipe.
Fermented for 4 days then into the fridge.
My concern is the water above the cabbage seal was dark brown, with something that looked like coagulated brown. I used a smooth stone from some river rock stone bought. I scrubbed it with dish detergent and a wash cloth. Then boiled for 30 minutes. My uneducated guess is oxygenation? All the cabbage under the, cabbage leaf seal, looks great. Additional jar seal above large cabbage leaf and stone was over jar top, a coffee filter, topped with a plate and weighed down the plate, then covered with a towel. So, what is the brown fluid? I carefully removed it with a spoon then, paper towel, then anything brown which was slight around top of good cabbage, then wiped inside of jar glass, then removed extra good cabbage to make sure any brown would be gone. PS: the fermentation raised the level in the up to almost top of jar. A half gallon jar, so came up about 3 inches, the smell is slightly sweet and vinegar. Once the brown above the cabbage leaf used to seal the chopped cabbage was all removed plus some good cabbage off the top. I nibbled about a 1/4 tsp 12 hours ago. Not dead yet!

[Christopher Weeks]

My guess is something came out of the rock.