I might be too use to coco by now but that soil looks like it may suffer from heavy compaction after enough watering.
The pic with the roots might be an early warning sign. The top section of the soil looks loose, but almost the bottom 3/4 looks smooth, the roots don't appear to have gotten much lower than the top section before taking a lesser path of resistance. But, the roots are not that old so this could be utterly wrong, maybe check around in the organic section, see some photos or ask some questions around there.