I've been feeding my corals with bio planktons and cyclope eeze a few times a week after the lights out. But recently I found this information on the web and cut donw a my feeding a little bit for watter quality. You can search yourself for more detail:
Mobile Invertebrates
Shrimp, crabs, brittle stars and similar mobile invertebrates will take the same meaty foods that are offered to fish. It is good to try to target feed them at least once a week. This also helps to ensure that they don't get too aggressive with their tank mates.
LPS corals
LPS corals are photosynthetic and will survive and grow with no feeding, but many seem to do better with occasional feedings. Most LPS corals, such as a bubble corals, open brain corals, elegance corals, etc. will take small chunks of shrimp or other meaty foods that are feed to the fish such as Formula One. Feeding once a week seems to be about the optimum frequency. There are a few corals, such as the bright orange sun coral, that are non-photosynthetic and require targeted feeding to stay healthy.
SPS corals
SPS corals never require feeding. They are all photosynthetic and live off the light. In the wild, they partake of zooplankton and some hobbyists like to try to simulate this natural food, but it is unnecessary and the fine food particles can cause a high load on the system.
Soft Corals:
Soft corals are mostly photosynthetic. Large polyp types, such as button polyps can be fed small items such as brine shrimp, but it is not necessary. Small polyp types, such as Sinularia, do not take any known foods, but may benefit from very small zooplankton type foods such as would benefit SPS corals. There are some soft corals, such as carnation corals that are non-photosynthetic and require targeted feeding of small food. These types of corals can be difficult to keep unless the hobbyist is willing to spend the time taking care of their nutritional needs.