corals extend their feeder tentacles at night.
I would feed my LPS
corals (to include open brain and lobed brain corals) after the tank lights have been off for a while because most of them extend their feeder tentacles at night.
PE mysis shrimp would be my food of choice. After thawing it and rinsing it a few times in RO
water I'd pass the shrimp to corals using tweezers. As soon as the mysis shrimp made contact with their feeder tentacles they would grab the shrimp from the tweezers and direct the food to the oral cavity (the 'mouth'). Other hobbyists use turkey basters or similar means to deliver food to corals (I used tweezers to ensure every mysis shrimp was seized by the corals).
Every now and then there would be a coral or two which didn't have the feeder extended but once they sensed the mysis in the water they would go and extend their tentacles (cyclopeeze also worked well to get them into feeding mode). For my set up I would turn off the protein skimmer and circulation for about an hour.
Small green open brain eating krill