I know we don't like to post pic's but they are worth a thousand words of help.
Anyway here goes, What you did is change the whole geometry of the DEEP WATER CULTURE system. You made it sallow, very shallow. Your plant has to be drowning, the only thing saving it is the air right under the rootball that needs air. How is the plant not sitting in water all the time. only the long roots should hang down into water. I just made the mistake of not doing what I know and it cost my bro about a 2 month set back.