Thanks Alf, in your experience what conditions does your P. damicornis like? I have mine about mid way in the tank, slightly off the center of the bulb (20L, 1 X 175W 6500K MH
and 2 X 28W PC
actinic), it gets moderate flow. It took it about 4 days to begin to polyp out on the bigger frag, the smaller one was putting out polyps from day one. I began feeding mush on Wed of last week (got the frag on Mon) and it began to extend it's polyps about Sat. It seems happy now, but it had me worried for a couple of days.