Is a 12 Hour Light Schedule Really Necessary?

[Reefer Matt]

Hey Reefers!
After passing out from reading my last electric bill, I decided to make some cuts in my home’s usage. One thing that came to mind was my six tanks that are on a 12 hour light schedule. So I adjusted all the tanks to a 9 hour schedule with a 4 hour peak.

And guess what? Nothing happened to the tanks. The alk and ph stayed close to the same, and the coral didn’t miss a beat. So this got me rethinking about my long held belief that 12 hour photoperiods were necessary for reef tank health.

With that in mind, what’s your schedule like, and have you thought about changing it?

 

[Üter]

 

[Üter]

I'm on the 12 hour. but only one tank. I don't look at electric bill.

 

[xiaoxiy]

I run a 13 hour photoperiod on my display and frag tanks for viewing purposes. My QT only ran at 8 hours without issue.

 

[Justfebreezeit]

6 hour peak, 8 total.

Reduced when fighting prorocentrum dinos and corals didn't mind

 

[MegabiteOG]

6 hour peak, 8 total.

Reduced when fighting prorocentrum dinos and corals didn't mind

I increased my white light intensity just to spite the prorocentrum dinos. It's not working.

 

[areefer01]

If you have not read the article below I would encourage you to give it a read when time allows. It will basically answer your question.

You can have light over the period of 12 hours but it does not have to be 100%. Remember the sun rises and sets. It is not a light switch and at 100% until someone turns it off at sunset.

On my system I did some calculations after reading the article and exchanging DM's with him. My lights peak at 85% for only 3 hours. Rest is ramp up, ramp down, and my average par is 187. I understand some hobbyist want to hit a PAR number but it really is just that. A number.

Dana at least did some real world tests to back up his article. Your mileage may vary...

Good luck. If all else fails go solar with storage. Short term budget hit but if done right should pay back within 6 to 7 years. Sooner if you live in the uppity states such as Ca and NY...

Edit: forgot the link, I'm a dummy...

https://reefs.com/magazine/a-differ...hotoperiod-spectral-quality-and-light-dosage/

 

[DmitryB]

If you have not read the article below I would encourage you to give it a read when time allows. It will basically answer your question.

You can have light over the period of 12 hours but it does not have to be 100%. Remember the sun rises and sets. It is not a light switch and at 100% until someone turns it off at sunset.

On my system I did some calculations after reading the article and exchanging DM's with him. My lights peak at 85% for only 3 hours. Rest is ramp up, ramp down, and my average par is 187. I understand some hobbyist want to hit a PAR number but it really is just that. A number.

Dana at least did some real world tests to back up his article. Your mileage may vary...

Good luck. If all else fails go solar with storage. Short term budget hit but if done right should pay back within 6 to 7 years. Sooner if you live in the uppity states such as Ca and NY...

Edit: forgot the link, I'm a dummy...

https://reefs.com/magazine/a-differ...hotoperiod-spectral-quality-and-light-dosage/

That's is super fascinating! I just wish I understood math beyond 2+2 so I could figure out my own set up!

 

[MegabiteOG]

If you have not read the article below I would encourage you to give it a read when time allows. It will basically answer your question.

You can have light over the period of 12 hours but it does not have to be 100%. Remember the sun rises and sets. It is not a light switch and at 100% until someone turns it off at sunset.

On my system I did some calculations after reading the article and exchanging DM's with him. My lights peak at 85% for only 3 hours. Rest is ramp up, ramp down, and my average par is 187. I understand some hobbyist want to hit a PAR number but it really is just that. A number.

Dana at least did some real world tests to back up his article. Your mileage may vary...

Good luck. If all else fails go solar with storage. Short term budget hit but if done right should pay back within 6 to 7 years. Sooner if you live in the uppity states such as Ca and NY...

Edit: forgot the link, I'm a dummy...

https://reefs.com/magazine/a-differ...hotoperiod-spectral-quality-and-light-dosage/

I agree. Great article. Thanks for posting.

 

[BriDroid]

I run a 12 hour parabola on my blues/violets and my whites run a 11.5 hour parabola. With only 1 tank, I don’t even care what the electric company says. I used to run 9 hours, but I like having the extra viewing time so I run them longer.

 

[mfinn]

Hey Reefers!
After passing out from reading my last electric bill, I decided to make some cuts in my home’s usage. One thing that came to mind was my six tanks that are on a 12 hour light schedule. So I adjusted all the tanks to a 9 hour schedule with a 4 hour peak.

And guess what? Nothing happened to the tanks.

This was over how long of a time period ?
A month or two?

I would think the accumulative effect would take 6 months, a year? IDK, just guessing.
And since you would be viewing the corals everyday, how much change in the corals appearance would it take before you noticed?

 

[Reef Jedi]

I run a 10 hour schedule with lights turning on at 10 am and off at 8pm. That includes a 1 hour ramp up and down so it’s really full spectrum/intensity for 8 hours. I run 4 Ecotech xr15 g6 pros. If I had xr30’s I’d run max spectrum for 6 hours instead of 8. I get good growth with this schedule. I’m not sure if I had electricity consumption in mind when establishing it. I was more concerned with the full intensity length being between 6-8 hours. Since the xr15’s are not as powerful as the xr30’s I’ve ran in the past. I figured another two hours on a full daylight spectrum would compensate. These lights are over a RS P500 so it is a deeper tank depth. Now that you mention this however I’d be curious what the tank costs me per month in lighting. I’m sure apex could tell me this somehow. I remember at some point putting in my electricity cost per kw hour. I have a feeling it’s less than charging my Tesla, that costs an average of $25 a month and I drive 40 miles every day minimum.

 

[alabella1]

I run a 12 hour parabola on my blues/violets and my whites run a 11.5 hour parabola. With only 1 tank, I don’t even care what the electric company says. I used to run 9 hours, but I like having the extra viewing time so I run them longer.

What lights are you running and controlling in hydros like that?

 

[BriDroid]

What lights are you running and controlling in hydros like that?

3 Quanta Helix bars, 2 Meso Blue and 1 Reef Crest Daylight.