Sounds like it is fragging itself. I had a similar situation happen to mine. Is there any visible rotting going on? You know when I met you the other day and you showed me a video of your tank, I was kind of thinking that the bubble stone is something you should consider removing. I didn't want to say anything at the moment. Most reefers have bubble traps in their sump to remove bubbles. It has something to do with fish and their gills getting infected. I'm not really sure. Do a search on micro bubbles and saltwater fish. They can also cause algae blooms. I'm wondering if this has anything to do with what is going on with your Kenya trees. Anyways I managed to save my kenyas by just the branches that fell off. I did cut the mother tree to stop it from creating a Kenya forrest. Just my two cents. Research the bubbles...Lou