Had this fella for nearly a year. As for watering, I wait for the moss to "dry out" meaning it's not crunchy and dry, but not feeling wet. The little white insects I spray off with the hose during the watering but they are persistent fellas. Nothing too crazy for maintaining him the past year.
Then on the last watering, I noticed a darkening spot and in a week, it's grown significantly. It feels crunchy, dead-like. I'm worried it's Rhizoctonia so going to get some antifungal today but I don't see any other black spotting. I'm actually pretty worried that somehow the root ball is dead and it's now dying from the inside...