I collect moss from outside and sometimes it stabilizes and does great, but most of the time with 2 weeks or so it molds. I am thinking there are a couple things happening: 1. The condition of the moss is not as good as it appears when I collect it. I live in Oregon and it's starting to dry out here so maybe the moss is past the point of no return even though it still looks pretty green?. 2. To much moisture in the build. But the only thing that molds is the moss, the rest of the plants in the build are fine and continue to do well - it just looks naked. I have not added isopods to any of my builds yet (the oldest is only 3 months old). They are definitely on my list of things to get and add. Until then, any other insights as to why only the moss keeps molding?