Don't feel bad.... something is wrong and you will find the answer soon..

I have seen sysems that run all the time and systems that just run every 30 minutes and everything in beteen.
I have soaked rockwool for weeks (on accident) and never seen it break up. I have seen algea completey consume systems and rockwool... the plants were still GREAT...

Growing should be easier than what your going through... Can you get someone who is an experienced grower to check out your set up.... There must be something fundementaly wrong and I bet it is a quick fix...

Have you tried hydrogen peroxide?
I'd still like to see the roots : )
good luck