Update! I took my golden barrel cactus out of the soil and to my despair it was completely rotted through! :'( I noticed though that when I took it out of the soil, the soil where the roots were was still wet. I'm assuming that's part of the issue. The water retained in the soil around the roots and rotted out the roots. I'm still unsure of the mold though. Luckily I so far have been able to save my Townsend barrel (that one I care most about). This situation is really bad though. Should I just buy a completely new bag of soil and maybe from a different company and buy some fungicide as well?? And should I have waited for the soil to be completely dry before I replanted my cacti???
