I just got a torch, and I'm very excited to now be among the cool kids. Checking it out at night, it' looks about the same as in the day, all wavy and peaceful. All my other euphyllia, frogspawn, hammer, bubble, they all curl up at night.
How come torches burn the midnight oil?
I can't say that "all torches" don't close up at night. IMPO more likely as it settles into your tank it will probably fall in line with your other Euphyllia.
Possibly the vendor you got it from as well had a different light schedule than yourself, meaning the "circadian rhythm" for lack of better terminology of the torch has him "close up a little later" Not sure if you've taken a late night leak and checked it then, my guess is you'll notice some retraction after a couple hours of lights out.
Also depending on their system, they might've had auto feeders, and or other things going off during the night, giving the torch a reason to "stay open" at night.
Not necessarily relevant but in nature, most corals actually stay OPEN at night, more specifically at dusk, as that is when the "feeding frenzies" start to occur with predator fish, and the corals stay open to catch the "spill off"
My torches when not splitting or creating new heads, have always retracted after lights out, sometimes slower and only after an hour or so.
But every torch and system are going to be individual, so there's not really an answer to this per se :) hope that can answer some of your curiosity.
