Refugium light times

[Ismellikefish]

How long am I supposed to leave the lights on in my fuge?

Some say 24/7 others say reverse cycle < I guess that means opposite of the main tank lights???>

Thx in advance

 

[mwwhite]

Yes - popular opinion is to run them opposite of your display tank lights.

The rationale is that it helps to reduce pH swing or overnight drop. Macroalgae in your 'fuge are photosynthetic, which consumes CO2 and releases O2. Obviously light is required for photosynthesis. As you may also know, elevated CO2 can cause pH to drop.