refugium question

[marxsman]

what is the appropriate time to run the lights on a fuge?

[Samper]

To control my ph swing I run my refugium lights from the time the display shuts off and until it comes back on. Digital timers are the easiest way to do it.

[Peterock]

So you have the light in the rufge. on when the display tank lights are off.

[Reefland]

Yup, it is commonly practiced. The purpose is to help offset the pH drop at night which normally occurs in the absence of light from photosythesis. If you light a refugium when the display is dark, photosythesis will still occur from macroalgae in the refugium.