This is the fun part of being new to this hobby. Believing adding two drops of something is going to magically cure anything. I'm really rooting for you bro, as ive been there before.
But at this point i feel i should clue you in to something i learned a long time ago. DONT TAKE SOME RANDOM's ADVICE without properly researching first!! you'll only mess your grows up over and over lol.
In your case your roots are to blame, more specifically your water temp. Not enough oxygen to the roots. Your roots being "off white" is a problem. And adding superthrive to the mix just fucked it all up. I hope i'm wrong. But ive been there.
Next time take the random's advice with a grain of salt, type it into google, see thousands of people saying "my res temps were xxx and adding superthrive made things go from bad to worse!!" And then go hit the ignore button on said random.
Back to your problem, your roots should be white if they are truly healthy. Even if you mix in used motor oil cause some random said to. Healthy roots = white. No matter what they're in. "But i use flora micro and i read that..." NO. White.
My suggestion is to look into live vs sterile res. google it. Spend a week learning something you will use for years. Then choose live res, brew a tea and you're done.
Remember i am a random as well and this advice should be taken with a grain of salt.
Good luck
