Are long photoperiods detrimental to your reef tank?

[Daniel@R2R]

So from what I've read, it seems a shorter photoperiod is usually what most people use on their reef tanks. I wonder if there's a reason we do that? I did some research on sunset/sunrise times over the reef, and it seems most of their photoperiods are a good bit longer than what we use. Based on that research, I adjusted my lighting schedule a while back. I run it for a total of 15.5 hours (with a 2.5 hour ramp up/ramp down on either side of 10.5 hours at peak light). Here's my schedule:

I guess my questions are:

1. How long do you run your lights and why?
   
2. Why do most people run lights for less time than there is sunlight on the natural reef?
3. Are there any blatant issues with my photoperiod?

 

[Brad Miller]

It looks like your peaking your light from 09:30 to 20:00, seems to me we would want to simulate a shorter peak period duration, am I missing something ?

 

[Sierra_Bravo]

I have a long photo period overall. Lights start coming on at 6:30 and go off at 10:00 PM. For a four hour period at the end, however, I'm only running a low energy blues spectrum. The tank gets peak spectrum from my LED's from 10am until 6pm, so eight hours, and my T5's are on in addition for six hours from 11am until 5pm.

I have no reason or guideline for why I did the schedule the way I did, other than it's what I thought would work based on seeing other's schedules and that the corals were responding favorably. The four hours of a reduced blues-only period was purely for my own satisfaction to allow me to look at the tank longer after work.

 

[Auquanut]

Following

 

[madweazl]

I run a 12 hour photo-period for the LEDs (1000-2200). They continuously ramp up for the first six hours and ramp back down for the final six hours. The T5s are on an eight hour photo-period (1200-2000). Peak PAR lasts all of three minutes.

 

[Rakie]

I run a 13.5 hour photoperiod, radion at 100% intensity. 1h ramp up, 5 hour ramp down, 8 hours peak.

 

[GrizFyrFyter]

I'm not a marine biologist so take everything I say with a grain of salt.

My theory for why aqua cultured corals do fine with shorter light periods is nutrients.

We maintain higher nutrient levels in our systems than in the ocean. If this equates to higher tissue algae populations then high nutrient corals produce more energy (and therefor more oxidizers as waste product), longer photo periods would be detrimental to coral health. They have to maintain lower tissue algae populations to avoid toxic oxidizer levels. In short, low nutrient system corals need more light exposure than a high nutrient system coral does.

Again, I have no education on the subject or evidence to support my theory. Just what I assumed based on seeing the difference of tissue colors from an Ultra Low Nutrient System (chased ocean numbers constantly) and a tank maintained at 5-10ppm no3, etc.

 

[AllSignsPointToFish]

I run an almost 12-hour photoperiod (1215-2330). The LEDs ramp up to target power in 105 minutes, stay at that intensity for 9hr45min, then ramp back down to zero over 90 minutes. The T5s come on in the middle of the photoperiod for about an hour.

 

[Rakie]

We maintain higher nutrient levels in our systems than in the ocean.

I would say as far as nutrients on a test, you are correct. But as they have live plankton 24/7, I might argue they have more nutrition/nutrients through direct ingestion in the wild than we give them.

 

[Bouncingsoul39]

I would say as far as nutrients on a test, you are correct. But as they have live plankton 24/7, I might argue they have more nutrition/nutrients through direct ingestion than in the wild than we give them.

They don't get plankton 24/7. The majority of plankton SPS feed on wells up from deep water and heads to shallow water at night. Hence, why SPS put out feeder tentacles at lights out generally, though they can be tricked to put them out other times. But your general point is correct, they are getting food particles in the ocean typically at higher abundance then what the average hobbyists feed though I'd say these days a lot of people are feeding their corals to boost growth.

 

[GrizFyrFyter]

I would say as far as nutrients on a test, you are correct. But as they have live plankton 24/7, I might argue they have more nutrition/nutrients through direct ingestion in the wild than we give them.

True. I think I could have more specific with dissolved nutrients and coral nutrition.

 

[Rakie]

True. I think I could have more specific with dissolved nutrients and coral nutrition.

It's okay, i did the same thing

They don't get plankton 24/7. The majority of plankton SPS feed on wells up from deep water and heads to shallow water at night. Hence, why SPS put out feeder tentacles at lights out generally, though they can be tricked to put them out other times. But your general point is correct, they are getting food particles in the ocean typically at higher abundance then what the average hobbyists feed though I'd say these days a lot of people are feeding their corals to boost growth.

Correct, I should have just said food particles in general!

Plankton reactors are apparently all the rage in Italy and some other parts of europe. It's interesting they are a huge deal in some places and never mentioned in others!

 

[McFly]

I run 6 hours at peak.

Here is the current schedule for comparisons:

7:00 AM to 10:00 PM - 15 hours total.

 

[Geebs19]

I run a 14 hour period.

 

[Dpate]

I can’t remember where but I’ve heard That the algae living in corals only photosynthesise for six hours at peak illumination.

 

[rkpetersen]

I run it for a total of 15.5 hours (with a 2.5 hour ramp up/ramp down on either side of 10.5 hours at peak light).

I also run a 15.5 hr photoperiod, 6:30 AM to 10 PM, although I run longer ramps than you and have 6 hours at peak.
Reasonable alignment with natural daylight, with allowance for my viewing habits.
Additional 4 hours of T5 midday.
Don't have any particular justification, but it seems to work.

 

[Daniel@R2R]

I also run a 15.5 hr photoperiod, 6:30 AM to 10 PM, although I run longer ramps than you and have 6 hours at peak.
Reasonable alignment with natural daylight, with allowance for my viewing habits.

Yep! That was basically my logic too!

 

[Flippers4pups]

Dana explains this in his presentation:



9 hours max for me.

 

[Charlie’s Frags]

Dana explains this in his presentation:



9 hours max for me.

Great presentation, which is normal from @Dana Riddle but I had the opposite effect in regards to lower par for my acroporas. All my acroporas slowly died when receiving less than 150-200. I didn’t have any success with acropora until I purchased a par meter and discovered I needed to upgrade my lighting. After that my acros started to A), survive longer 2-4 weeks and B), finally encrust and grow. That’s just my experience in my tank and I have no scientific data other than my current par measurements to offer. The growth of my monti’s zoas and lps exploded as well with the higher par values. Just my $0.02

 

[ChaseBurke]

@mdbannister I run almost the exact same schedule as you. I run from 7 to 10, have a 3 hour ramp up/down, and t5's come on from 9:30Am to 8Pm