all jammed together and brownish.....you need to break apart the rootball and get some oxygen to the roots....carefully....

You need to use either hydrogen peroxide (3% at 2 tsp/gal every other day) or a good quality zyme product and use it asap. Keep your ppm low at 800....watch and adjust ph carefully.

Let us know if you DO see any improvement at all. But Deja was right.....the issue is roots and not enough oxygen.