Growth Problem

[pineapple_dreamer]

Hi,

Im still consider myself as newbie in hydroponics. Started 2 years ago, failed to produce good result until today.

http://i989.photobucket.com/albums/a...psasy4lalp.jpg
This photo taken about 2 years ago. Its a kai-lan. Took more than 3 months for it to grow until this height. PH level around 5-6 and around 1500 ppm. Using floating raft DWC method. Using A B solutions. Temperature is around 28-33 Celsius for whole year. The stem are not straight.

http://i989.photobucket.com/albums/a...ps7vodz7mj.jpg
http://i989.photobucket.com/albums/a...pst4szfcla.jpg

i took these 2 photo recently. Started since mid August. Using ownmade DRFT method. Those are curly mustard. Same ph level, ppm and temperature. May know where is my mistake?