How long should your fuge light be on for?

Like the title says? How long should I leave the light over my fuge on. Im using a 75w 65k HD bulb.

 

I would say you have 2 good choices:

1) A reverse day/night cycle. In other words, set your fuge lights to go on when your DT lights go off. That way, the plants in your fuge will produce oxygen while the ones in the DT produce CO2, and vice-versa. This helps with the O2/CO2 balance in the tank.

OR

2) Leave them on all the time.

I go with option 1, myself.

 

i do the 12 on 12 off thing myself as well

 

I also do reverse lighting

 

i never turn my off

 

Mine are opposite my display tank lighting to help maintain a steady pH.