I have grown like that once. Just like ForgetClassC said I used another bucket when changing nutrients.
When the plant starts drinking a lot I stopped changing buckets. It seemed to drink a bucket in a day or two. I just topped fed the plant with the proper nutrients and let it drain to the bottom.

I just re-read your post, you do use two buckets, its when you are changing the buckets you are having trouble... Your root mass must be massive.
Mabey next time drill a hole in the bucket you can use as a drain and then just top feed the nutrients so they fall to the bottom.
The picture looks good. I was actually wanting to see how much it stretched. It did not stretch to much. That is a good thing. The LED light you are using is working nice.
Thank you for posting a picture.
demoreal Reviewed by demoreal on . LED UFO 90 Grow Nirvana Northern Lights from seed......one week on 12/12 cycle (pre-flower female)....5-gal bubble system (air pump only-no drip)....GH nutes- standard phase feeding program per GH chart......UFO 90 led light 16" off the plant top........GroLab GL80......no fan venting system, minimal heat build up with LED, just open the vent flaps during the day and let the air circulate. Vegged for 4 weeks. First attempt with bubble bucket. Super easy and very quick growth. I thank you guys for your Rating: 5