For those thinking of keeping Pectinia in their tanks. This is a very resilient coral; however, it is also a very aggressive coral. In the picture above, the Space Invader has been in my tanks for about three or four years and was grown from a 1/2" frag. Currently, the coral is about 6 or 7 inches in diameter. The Rainbow has been in my tank for about 1 1/2 years and has colored up a bit, but only grown about 1/2" total. Here are my observations concerning pectinia:
Lighting: Moderate to Low seems to work best. Water Flow: Moderate to Low...Lower end works best for me. Placement: Low in tank, at least 6 inches away from any coral, and on a rock that can be easily moved as it grows. Temperament: Very Aggressive. According to online resources the pectinia will put out 3 to 4" sweepers. I've witnessed 6" sweepers on my space invader. This coral is a the bad A$$ on the block and will easily kill anything it touches. I used to have a galaxia and I think I would give it a run for its money on killing. This is why I recommend a movable rock. Water Quality: Standard parameters for 1.026 or 1.025 Salinity marine tank. Of note: this coral really seems to like nitrates in the water column. When I was dosing Potassium Nitrate, this coral was inflated the most I've ever seem. My space invader has tolerated some really big swings in water quality and tank temperature. The exception in Alkalinity. If the alkalinity drops to low this coral will deflate almost completely and start dying shortly after. Feeding: Although not necessary to feed, the coral loves meaty foods similar to other LPS corals. I also think it helps with growth.