I think clones turn to much like that when that part sits water to long and doesnt get proper oxygen. I have found the best way to clone is to create an environment that has a warm root zone (75-80 degrees) and humid while at the same time getting fresh air. Like with a humidity dome with holes cut on the top. Maintaining these conditions and being patient will lead to rooted clones.

Here are some pointers when taking clones.
1)Cut them at a 45 degree with a razor that was just cleaned with an alcohol moistent paper towel. Repeat for each clone taken to ensure a clean cut.
2) Dip each clone in cloning solution or gel and place in medium. In your case the bubbler. Make sure its light proof so alge doesnt grow. Heat water to about 76 degrees. Give them a spray of water and then just sit back and wait. If thye dont perk up after you cut them put them in a humidity dome with some holes for air.
3) be patient. dont poke at them 3 times a day every day.