Can I make Bubble Herbal Extract with moldy plant matter? YES. Bubble Man recommends an extra mold-removing step: place your herbal extract into a jar full of water with a tight-fitting lid and shake it up. The mold spores will float to the top and can be skimmed off with a spoon or turkey baster. Then, rinse the jar into the 25 micron bubble bag and press the moisture out as usual.