Please Help me with this root problem !!!

Dear forum members and fellow growers,

I changed reservoir water and roots seemed to go to brown overnight, I have read some posts about the subject and I am not sure if it is brown algae or is it rot or are they just stained, one of them seem to be more brown the other. Roots dont seem to be slimy but they at some bits a bit soft.

I have made some pictures, hopefully clear enough, with system in place it is kind a hard to reach down there.

If it some kind of rot what can I do about it???

Look at the root tips, if there black you've got a problem.
my nutrient solution usually stains my roots.
One of the most important things in hydro it keeping things clean.
I clean every thing with a h202 solution weekly.

Hi

No, there doesnt seem to be any black colour around the roots, but still they made me worried, plants seem to be healthy

Please anyone else with knowledge on this problem???