Light duration


Active Member
Have been reading over on -- about reduced light schedules and lights out a day or two per month. Seems there is some validity being given to the theory that SPS coral grow more at night. So my question to you that have SPS experience what is your light schedule and do you indeed leave the lights off once in a while to simulate some cloudystormy days, and what is your opinion on the growth of SPS because of this?


Active Member
I honestly think the corals open up at night and "feed" using their polyps at night. My opinion on growth is leaving lights off a day a week or month may be valid -- but probably minimal at best when you consider the benefits of proper lighting, calcium and water parameters.
Something to experiment with -- but in all reality you would need two tanks on the same system, one being a control group (timed regular lighting) and other a test group (lights off a day a week/month) and measure growth rates on the same frags of the same size to start with. Be interesting but not really feasible in the home systems unfortunately.

nano reefer

Active Member
it makes sense. with the lack of light, they are forced to eat. and with no light at all it will need more polyps to feed it, so it would grow itself more.
i dont have SPS, but i sometimes turn my MH light off. i also play with the timers.