How come my jars started growing mycelia, but for some reason have stopped?
Mycelia can stop or slow to a halt for various reasons.
Mycelia can stop or slow to a halt for various reasons. Some can include: drying of the substrate, an overly wet substrate, internal temperatures in and out of the recommended ranges, substrate that may have been "cooked" by direct heat during the sterilization process, etc. Generally, the bottoms of jars colonize much more slowly than the tops. So if you have slowed growth around the bottom/bottom sides of the jar, an easy method to help kick -start the mycelia is to "flip" jars. Simply place them on their lids, resting on the dry vermiculite layer. This should act as a vacuum, forcing CO2out and fresh O2in the jar (as CO2can build up in jars). The cake will slide down, forcing air out and, by the laws of physics, drawing it back in as well. (Can't have a negative space of air, the jar itself is not sealed). Other factors that are not so easily "cured" are the ones listed prior. Generally, you cannot add materials to colonizing substrate without risking contamination by opening the jar/breaching the vermiculite layer. Avoid these possibilities by mixing your substrate as evenly as possible (to avoid over -/under - water content), keeping the jars incubating in a not too dry environment, keeping the jars stored in a warm area (not hot, not cold), and also making sure water does NOT splash on your jars if you elect to boil to sterilize. Water splashing into the jars can make them too wet for the mycelia to colonize.