Is this root rot? (DWC, omg pics)

[Paranoid]

Hey there,
This is my first DWC setup.

They are 17 days old now, their 9th day in the bubbler. PH is at 5,5. I hadn't measured the ppm for a couple of days and it had tropped from 280 to around 70, so I raised it to 490 to see how that goes.
But that's not my problem. I believe there might be root rot developing, but not sure, so here are a couple of pics:

Might that be root rot developing right below the pots there? And what can I do to fix it?


Bonus pics comparing today and a week ago, massive growth. You can see I topped them two days ago.

 

[ol hippy]

Are you using organic nutes ? If so thats the color your seeing if not ...well I don't have that knowledge.. But someone here does and I'm sure will be here shortly !!

 

[RPsmoke]

Hmmm... hard to say this early. What nutes ?

Hows the smell ?? When all else fails, do the smell test ! Root rot stinks. Any "bad" funk in the res usually gives off a nasty odor.

Can you feel any of the brown "stuff" ? is it more slimy/icky ? Or hard and sand/gritty like ??

Plants seem to be growing great.

What temps ? You know the temps in the res by chance ?

When was the last full drain and replenish ?