Oh! Your actually growing them in soil!
That may make things more difficult!
I've had good luck with actually just using the hose to excavate plants that are plant in actual soil, especially if the soil is saturated, konjac shouldn't mind that level of moisture.
Water is almost always a very gentle way to get roots loose from heavy, fine soil, the kind I have here, and I think you should have up there.
Just a thought
