Help with Coralife Digital timer

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Aquarium Advice Activist
Oct 22, 2005
Nevada, USA
I just received my Coralife digital timer, and i am not able to program it.

I need to turn on my CF daylights at 8.00AM - 1.00PM then back again on 3.00PM to 10.00PM. When these lights are turned off, i want lunar nightlights to turn on. The way i programed it was

All Days selected
cycle 1: ON 8.00AM, OFF 1.00PM
cycle 2: ON 3.00PM, OFF 10.00PM

I turned it on, and it started my night lunar lights. What am i doing wrong?

Thanks in advance!
This is probably a stupid question, but you are plugging the CF lights into the yellow plugs, right?

I have a Coralife timer, but mine isn't digital, so I can't help with the programming.

Also, with mine, the nightlights (or whatever is plugged into the nighttime plugs) come on when the daytime things go if the time is during when your daytime lights are off (its after 1pm here), the nightlights will probably come on. I'm not sure if its like mine or not though.

Hope that helps a little...
Plug your lunar lights into the blue recep. With this timer you can program when the yellow receps turn on and off then the blue recepts will do just the opposite. When the yellows are on the blues are off. When the yellows are off the blues are on.
Yeah i forgot to tell you that I have plugged daytime lights correctly in yellow colored pins and lunar lights in blue colored pins.

The lunar lights were turned on when i turned on the timer (11.30PST) instead of daylights turning on.

The mode was set to OFF. I changed to AUTO but still no luck.

Any other ideas?
Quick question... when you put the mode switch in "off" does it turn off the day lights and turn on the night lights. When you put the mode switch in "on" does it turn on the daylights and turn off the lunar.
So then it would just not work properly in the auto position?? Is this correct?
Thanks for getting back, When i switch to ON mode then daylight turns on and lunarlights turns off. When i switch to OFF mode then lunarlights turn on and daylight turns off.

I think this is working correctly, not just the auto timer am i right?
Well it sounds like you have it hooked up correctly except when you go to auto it's not working properly.
I've had this exact thing happen to me too. When I put the mode in "off" it worked like it was suppose to. When I put the mode to "on" it worked correctly. When I went to "auto" the daylights wouldn't come on like they should have???? Finally I decided my timer must have been bad so I left it hooked up and in the auto position and went to bed. The next day when I woke everything was working properly!!! No bull... the lights automatically turned on and off in the auto position. To this day I have no damn idea why they(I have two timers) didn't work properly that night. Since then they have been working perfectly and I was thinking maybe it just needed to reset itself. I think you might be in the same boat. I'm VERY curious and will be watching this post.
I think you are correct, it might need 24 hours to cycle. I was reading the instruction pages and in troubleshooting it is mentioned.

--Daytime light do not turn on.
NOTE: If present time is past the desired daytime cycle "ON" setting. Let the power center cycle for 24 hours.

Will wait and check tomorrow and post results.

Thanks for the help
Ok! Now my timer is working fine. I think it just needs few hours to reset itself to the cycle set.
I have 2 different timers, one is a Coralife and can't remember the other brand name. Both look alike. But one thing I noticed is that on one, the ON means the moonlights are on, and the off means the moonlights are off. Complete opposite to what I was thinking to be correct. It kind of threw me off at first.
I have the same timer, It seems that the timer does not check the time constantly and only trips when it crosses the time that you program in. So, when the time crossed 8:00AM it turned on the circuit, and the next time it crossed an off point it turned off the circuit. It did not "realize" that it was in an on section, it only activates at the crossing points. HTH anyone else confused.
i just wanted to say thanks to the OP. i just went and bought one and it worked just like you said it would. saved me from asking the same question.

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