I hate to break it to you but they are one of the most advanced corals there is. They are nearly 100% aposymbiotic and feed on either zooplankton, phytoplankton or both. Very strong current is necessary, a powerhead pointed right at them can help, but if it is not at the exact velocity they require from the exactly correct direction they may not feed. An almost constant drip of phytoplankton and multiple (minimum two)daily zooplankton (artemia) feedings are necessary. They eat constantly. Try and position them in an overhang that is accessible for feeding but has limited light. They are drop dead gorgeous and a lure for reefers, but alas, their record is poor.