What adaptations does it have for withstanding saltwater? Or does it efficiently capture freshwater from the rain? Since it can absorb nutrients from the ocean to fuel its growth, that would suggest it has at least some tolerance to saltwater, so how much tolerance it has, and ideally some vague mention of its mechanism, would be good.
These aren't effectively part-fungus like some crystalflora, so is it really a detritivore any more than Earth plants usually are? Is it like certain kinds of plants that can adapt to the unique substrates of part-decayed compost or rotting but recognizable logs?
I like the detail about the shrog skeletons.