Hey Jax,
I just noticed your thread.
A word about roots,
they do all kinds of weird stuff, pearly white ones are nice, but offcolor roots are not necessarily an issue.
Many additives discolor roots.
If I see something about the roots I don't like, I will give them a good rinse with the hose or a few dunks in clean fresh water and put them back in a fresh rez.
Slime, debri, and smell are all root zone issues that should be addressed as they are noticed.
Usually you will notice something off with the leaves, before noticing a problem with the roots.
In this case oldster almost certainly nailed it, as too strong of a solution.
Plants are looking pretty good by the way!