Notice the bite marks.



From the photos.... They seem to love greens quite a bit.... however, please do remember this is not a substitute for providing them with their normal protein intake.
I feed a wide range of foods, from frozen bloodworms, frozen brineshrimp, frozen krill, frozen mosquito larvae, tetra colorbits, new life spectrum pellets.. along with many vegetable greens, cucumber and blanched zuchinni... etc. The idea here is to get them to accept a wide range of food products so as to be able to vary their diet somewhat. You just have to try.
As with all foods, this should be provided sparingly, and any uneaten foods should be removed before spoiling and fouling the tank water. I usually leave it overnight and remove the next morning along with the morning water change as I siphon out the remaining bloodworms and brineshrimp.
If you are having trouble getting any of your fishes to eat... I would check other issues with the tank such as water parameters, stress from aggression/fear from other tankmates, relative security and or shyness, limit the amount of disturbance in the tank, provide a cover/blanket to encourage privacy... provide hiding spots, caves.. etc... these are just some of the things that can influence how a fish will behave in its surroundings. Once it feels safe, secure, and comfortable.. it will begin to forage for food.