There are a few organic fish foods on the market, but they are very expensive and hard to find. Also, since many of these foods are also vegetarian, a platy will not do well eating them. Fish need certain things in their diets and trying to make them eat as we may can certainly damage their health.
MM
they can eat leafy foods like spinach and swiss chard, but they would really need some meet in their diet like fish meal which is found in flakes andf pellets.
But they can eat leafy foods. just place it on a aquarium clip.