I have two. They eat Spinach, Kale, collard greens, red Lettuce, Romaine Lettuce, vegetables, fruits, rose petals, dandelions,
You have to be careful with the types of flowers they eat. They also graze on the grass in my yard.
NOT iceberg Lettuce there is not enough vitamins in there for them.
There is a calcium sprinkle that I also add to their food at least twice a week.

What do manta rays eat?