When should i start w/ the skimmer?

[Habitat]

I started my cycle this past weekend. I'm running the power heads over LR along with a hang-on canister filter at about half output. When should I start running the Protien Skimmer? Also, how many hours of light should I use while cycling?

20gal. 14lbs tonga, 5 blue hermits, 2 red hermits, prizim protien skimmer, 2 pwr heads, H.O.T. magnum hang-on canister, and 175w heater, 96watt coralife quad.

 

[dralarms]

I'd go ahead and start it. May not get much to begin with but I think it'd be better to have it running than not.