rotting roots ?

super lemon
1st-2nd weeks of flowering
nutrtion- organic bio bizz
i waterd it every two- three days, and last week i noticed the top of my fan leaves curled up and down and there is starting to appear some spots on it , and its spreading!
it's in a 2 galon pot... is it rotting roots ? and if so... is there anything that i can do to save it? plz help!!

Yeah, doesn't look good.

I would put something under the pot to get more airflow between it and the water tray. Also a fan blowing at the pots would help.

It looks like straight peat or coco, I would add perlite next time.