Multiple light cycles a day

rkcca · #1 10/03/2007, 08:40 PM

Would having two four hour daylight cycles over a frag tank during a day promote more growth over a single eight hour cycle?

I'm willing to give it a try. Does anyone have experience with this technique?

JetCat USA · #2 10/03/2007, 08:54 PM

i had a remarkable increase in growth with a 6 hour on, 6 hour off cycle (2 photo periods per day), the only down side was fish seamed allot more stressed, over a frag tank i don't see where you'd have any of those problems.

JCTewks · #3 10/03/2007, 11:27 PM

can you attribute the growth directly to the photoperiod, or were other changes made at the same time?

JetCat USA · #4 10/03/2007, 11:57 PM

just the photo periods. there was a study done that was posted several yrs back (sorry i don't recall whom it was) that stated coral growth (actual depositing of CaCO3) came during the dark hours, and their CaCO3 uptake from the water that was to be deposited happened after 3 hrs of lights (less then 3 hrs and you get no growth) and declined sharply after 5 hrs (longer then 5 hours minimal CaCO3 was taken in by the corals).

with that information i went with the most logical of 6 hrs on, 6 hrs off and i got 1.5x the growth out of most SPS and a few Monti's were 2x but as i stated my fish seamed much more stressed.

rkcca · #5 10/04/2007, 12:48 AM

I'm mainly trying grow out zoas. JetCat, Did you have any, if so did growth accelerate?

airinhere · #6 10/04/2007, 02:23 AM

I do this on all my tanks.

On at 8 am, off at noon. On at 5pm, off at 11 pm.

I keep SPS, LPS and softies in my various tanks.
I have out of control growth of all my zoanthids and mushrooms. Soft corals have decent growth, but look great.
LPS include Bowerbanki and Hillae acans, platygria, frogspawn, Duncans and several types of chalice. All exhibit rapid growth patterns.
My SPS actually have changed colors and look nothing like they did when I got them.

(Much of my stuff has turned mettalic and neon colored.)

Cons: I think my colors are not as deep as I would like them to be. But I attribute this to my lights not being the perfect color for my desires. (20K SE 250W halides.) Looking to change to Aqualine Bushke (sp?) next light change. (Using Hamilton 20K currently.)

Growth seems to be in spurts of amazing speed. Usually when I have been feeding heavily for a week or two. Suddenly I get another obvious growth ring around all my chalices and numerous new heads on my Duncans. Or my SPS start growing like weeds. Usually Lasts a short while as I find it hard to keep up with my tanks demand for calcium like I should. (I need calcium reactors for all my tanks badly.) Plus heavy feeding leads to water quality issues.

And since I think you should see the results of the experimental reefers efforts, here ya go.

These are some of my Zoas I am preparing to take to a local frag swap.

These are my two 90 gal tanks

If left as they are on the sandbed, I estimate about 3 months and I would have no sand showing at all. Probably less time than that.

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Photo Sharing and Video Hosting at Photobucket

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rkcca · #7 10/04/2007, 02:39 AM

Wow, Ok, I just setup another daylight cycle. I report back on growth. Thanks

redox · #8 10/04/2007, 05:21 AM

I run a double cycle in the greenhouse as well. I did it not for growth but to cut back on heat in the hottest part of the day. Didnt know it improved growth rates but if so good

JetCat USA · #9 10/04/2007, 07:00 AM

yes zoa's growth rate increased as well but not double.

Quote:

Originally posted by airinhere
I do this on all my tanks.

On at 8 am, off at noon. On at 5pm, off at 11 pm.

i had great colors and my best guess as to why you might not is the short 4 hr light cycle and the two cycles being uneven. corals prefer stability and your 4 hr then a 6 hr photo period is like a seasonal shift every day. go with two 5hr or a 6hr on/off and you'd prolly get better results.

airinhere · #10 10/04/2007, 02:09 PM

Y'know, sometimes the obvious is staring you in the face and you just dont see it. Uneven light cycles makes sense. I might have to slightly modify my light cycle.

Don't get me wrong, I am very pleased with the colors I am getting, but from my own perspective, I think the colors should be fuller.

JetCat USA · #11 10/04/2007, 02:36 PM

even em up and let us know in a couple weeks if you notice any change.

bristle · #12 10/04/2007, 07:39 PM

Quote:

Originally posted by redox
I run a double cycle in the greenhouse as well. I did it not for growth but to cut back on heat in the hottest part of the day. Didnt know it improved growth rates but if so good

You may not see results because the calcification takes place in darkness, not when the photosynthesis is occurring. This is just assuming that the hottest part of the day is also the brightest.

At least this is what I see from the others.

MJAnderson · #13 10/04/2007, 10:18 PM

Interesting, since I have an all sps frag tank. If I was running 8 hours before (but was thinking it was too much light since I had 400w 14ks) is 6-on 6-off worse or is it the duration, not the total hours per day, a coral is under the lights?

JetCat USA · #14 10/04/2007, 10:25 PM

the 6 on/off isn't the same as having the lights on 12 straight, you'll be fine with it.

craab · #15 10/05/2007, 06:23 PM

I'll give it a whirl as well on one of my frag tanks.

7am-1pm

5pm - 11pm

I'll post pictures and a log to my blog if anybody is interested in following.
Blog

airinhere · #16 10/05/2007, 07:02 PM

My reasoning behind using a dual light cycle was twofold.

1. I am cheap and have about 3000W of lighting (cumulative) on all my tanks. And I live in California. I wanted to try something to help keep my electrical bill to a reasonable level. (Non-Peak hour usage!)

2. I had read that after the first 6 hours of light, most corals hit a saturation point where additional light doesn't really do any more good. 12 hour photoperiods are more realistic for our corals, but I interpret this to be more like helping to set their circadian rhythyms. I also had learned that much of the physical growth of a coral takes place at night during the dark cycle.

Working off these concepts I theorized that by giving my corals a 5 or 6 hour long exposure to light and then a similarly long dark cycle twice per day, I would be able to essentially get twice the growth out of my corals. (Not quite that simplistic, but thats my basic desire.)

I do not concern myself with the unnatural circadian rhythym that this will doubtless create. Instead of a natural cycle, my corals get a cycle I have designed for them. And one I feel would work in the wild if only we could change the length of a day for our corals. I do punctuate the traditional circadian rhythym with an extended night period during the actual nighttime. (11:30pm till 8 am.)

Another interesting side note:
I have noticed that I am able to immediatly introduce new corals into this light cycle without fearing light shock so long as I put all my new corals on the substrate for a week or two and then slowly move them up. It is my understanding that traditional light cycles have to be altered in many instances when a new coral is introduced. (especially light sensitive or bleached corals.)

I do have to be careful not to turn my lights on for too long. If I am home for the afternoon, I sometimes turn my lights on during the day and end up light shocking my corals sometimes. (8 am till 11:30 pm is a little bit too much light. [15 1/2 hours]).

Leonardo's Reef · #17 10/06/2007, 05:06 PM

JetCat USA, I have 2 tanks in one room, one frag and one display. If I go for the multiple cycles my frag-tank will be "dark" during the afternoon.
However, the tank will be indirecty lit by the display (just a little) Does it have to be completely dark to let the corals calcify, or can there be some light?

Thanks, Leonardo

JetCat USA · #18 10/06/2007, 07:02 PM

there can be some indirect lighting, you don't want excessive. at a max you want it to be the intensity you'd see on a full moon night with a clear sky.

Avalanche Wolf · #19 10/07/2007, 08:49 AM

i have started this 3 days ago and I have already noticed a differance in the zoas. They seem to have more extention and just verything is more happy it appears.

Thanks for the tips

Leonardo's Reef · #20 10/07/2007, 03:41 PM

Quote:

Originally posted by JetCat USA
there can be some indirect lighting, you don't want excessive. at a max you want it to be the intensity you'd see on a full moon night with a clear sky.

Ok, thank you. I'll make sure the tank will be as dark as possible

Leonardo

InADream · #21 10/08/2007, 07:10 PM

This sounds like a great lighting cycle, only thing that I am worried about is how do the fish take it... Is there any extra stress on the fish...

Dream

airinhere · #22 10/08/2007, 08:07 PM

Maybe. But I do not think so.

My experience is that it does not seem to have any impact on the fish.

I am trying to breed PJ cardinals (maybe Banggais later on) and I have around 20.

Also have Yellow tangs, chromis, fiji damsels (blue w/ yellow belly & tail), saddleback, cinnamon, maroon and ocellaris clowns, sleeper goby, mandarin, lawnmower blennys and scooter dragonettes.

So far no wierd behavior.

No babies from the PJ cardinals yet. (only 4 are old enough to anyways.) When the PJ cardinals or clownfish pairs start having babies, I would be confident saying there is no side effect of the dual light cycle.

JetCat USA · #23 10/08/2007, 08:26 PM

it was posted above, fish are stressed by this.

InADream · #24 10/08/2007, 08:40 PM

I would love to hear from a few people who are currently using this cycle... Not to go against what JetCat or AirinHere says just want to hear some opinions...

Dream

airinhere · #25 10/08/2007, 10:06 PM

Jeycat, not to be argumentative, but how exactly are the fish stressed? I am assuming you are speaking from personal experience. What were they doing (or not doing) to show their stressed state?

I ask because I have experienced no real issues with the dual light cycle. Everyone is eating like pigs and behaving in their small communities like model citizens. Although in all fairnes Cardinals are kinda wierd in the first place.