Hammers when lights go off

[aqua_dog]

So I keep seeing these pics of corals online while people blues are on and they have their sweepers out, they look full etc. but when my lights cycle to blue at the end of the day, my two hammers retract like two scared turtles. Is this just because they are photosynthetic and do that because there is no lights? could I keep the whites on mixed with blues? I have a 20 gal nano with a aqua illumination nano LED light. there are three settings, whites, blues and royal. all are about 80%.

 

[thegrun]

They close up at night when there is little or no light.

 

[Sk8r]

Is a light switching off to switch the blues on or is the blue level constant even while other lights are on? Blue light is intense light. Many people think of it as 'cool' and therefore gentle, but it gets to depth.

 

[aqua_dog]

Is a light switching off to switch the blues on or is the blue level constant even while other lights are on? Blue light is intense light. Many people think of it as 'cool' and therefore gentle, but it gets to depth.

It is usually constant but I have them set so they gradually decrease to a "night mode" and they are essentially off.

 

[Sk8r]

SO no possible spike in intensity, always diminishing. Maybe it's so low they're treating it as dark. But be very careful of burning them, even with blues.