Lights on/off during cycling

[christian1971]

Does it matter whether the aquarium lights are on or off during the cycling period?

[Elite Aquaria]

I have always cycled my tanks with the lights on since some tanks have fish while others do not. I have never had any issues with a 4 week cycle.

[ericatdallas]

It shouldn't matter... if you have no plants and/or fish in it, keep it off.

[christian1971]

I think I will keep them off.