Coral reaction to lighting

[MikeyZo]

Has anyone noticed, specifically with LPS like euphyllia or some acans or Blastos, that there’s a certain time later in the day that they start to shrink back, almost like they know the lighting is going to change (like a midday to evening light setting)? Kind of like an internal clock? Or is that a sign that they’ve had enough light and maybe Im keeping it on a tad too long?

 

[TX_REEF]

I noticed that with LPS and also with anemones to an extent. It did seem to subside when I reduced the intensity of my lighting. LPS especially need way less light than most people think, 150 PAR or even less will do just fine.

 

[MikeyZo]

They’re on the lower part of my tank but I have some sps and a clam so I have to keep the lighting a little on the brighter side

 

[TX_REEF]

may be worth checking the PAR there if you have a concern. If they are happy most of the time, I wouldn't sweat it.

 

[Rocks reef]

They extend and retract based on the amount of light they are receiving. My euphyllia are open when the lights come on, but they extend farther as the light ramps up. During the ramp down period, when the light hits a certain intensity, they begin to retract. It is normal behavior.