Does photoperiod influence coloration?

[ctripi]

Is there a possible link between duration of photoperiod and coral coloration. Could shorter photoperiods (6-8hr) contribute to brown sps coloration by inducing the coral to harbor a denser zooxanthellae population? Conversely, could longer (10+hrs) photoperiods contribute to better coloration? Any thoughts ? I currently run 14k 250w hamiltons for about 8 hours, 10" above the water of a 20" deep tank. My sps have good colors but mostly at the more actively growing branches.

 

[o.c.d.]

Corals are predominantly brown because the zooxanthellae they contain are brown due to the fact they absorb most other colors. Zoox contain pigments involved in photoprotective dynamic photoinhibition ,which in effect absorb excess light and keep it from stimulating photosynthesis. These pigments absorb blue wavelengths,not red.Since zoox don't have the ability to rapidly photoprotect against increased red light,they may bleach when suddenly exposed to red radiation.Riddle's experiment with red light bears this out and suggests that red light might play a role in regulating Zooxs pigmentation and density.
I personally think you'll only notice more growth in the coral as to the color in my experience making the colors change is all in the bulbs.You could add some T5 bulbs like fiji purple and really change the looks of the coral,and the rock,ect

 

[ctripi]

What is the Riddle's experiment you've referenced. Anyone else have any thoughs ?

 

[o.c.d.]

It's referenced out of The Reef Aquarium Vol.3 Delbeek & Sprung.The lighting chapters have lots of info but I think your question on denser zoox is still being discovered.The info in the book about Total light received by the aquarium fails to mention anything about color.It describes how to figure out if the light intensity matches nature in simple equations,To me this book does have a very indepth chapter on lighting, It covers Orientation of marinelife, Skylight vs Sunlight, Total Light Received by Aqua,UV light,Lighting Parameters, Coral Coral Colour,Response of Coral to artificial lighting and more the book is IMO very good. Riddle also showed that low water motion limits photosynthesis in zoox,even when light intensity increases,So the effects of lighting has to be viewed from a combination of aspects. Trying not to ramble

 

[ctripi]

What is the publishing date of the Vol3 ? I have volume one and was quite pleased. Can you compare the light chapters to that found in Eric Borneman's Aquarium Corals ?

 

[o.c.d.]

Publishing date is 2005,and lets just say 74 pages in Vol 3 to cover lighting and maybe 8 in Bornemans,

 

[ctripi]

Looks like I might have to sneak a textbook purchase past the wife. Thanks for the tip.

 

[FunkieReefJunkie]

I've witnessed in a high end coral store an interesting phenomena that I at the time regarded as a means to keep tank temperatures down, but now think played into the success of maintaining vivid coral coloration. We all know corals receive a burst of energy from lighting and beyond that set amount of time the lighting is unharness-able, even detrimental. The corals need a time out so to speak. The shop kept 400 watt lights over the tanks that would be turned on and off every thirty minutes. Those display tanks were full of gorgeous colored sps and they weren't deep tanks. Personally I think high intensity short burst lighting would be fun to experiment with if my electricity bill didn't factor in.

 

[o.c.d.]

Interesting how about the lightrail or mover that would be similar to short burst.I'm in the process of setting up a prop tank with a light rail and will be able to adjust the mover to pause at each end of the rail,I'll have to play with the delay time and see if I notice any difference.

 

[FunkieReefJunkie]

Ah yes I have two lightrails carrying 250 watters each. I'm not getting the intensity I want to play with. The light rails are set on to go back and forth for thirty minutes and off for 30 minutes. Believe me I'm toying with the idea of at least swapping out one of the 250 watters for a 400 wt preferably in the 20K range. But then again I've been meandering on the idea of adding in some T5's for some light continuity and added pop.

The problem with my current scenario is everything in the back row under the Radium looks fantabulous. Everything in the front row under the Iwasaki looks craptastic but grows well. What I've been doing is letting frags grow out in the front and then shifting them to the back to become pretty again. Takes a fair amount of patience to watch this play out.:strange: Kind of like watching paint dry. :lmao:

 

[hahnmeister]

Click on my red house... I use a light rail on my main tank. It works very well.

 

[FunkieReefJunkie]

Hahn I thought you were considering going all T5? There is no doubt light rails are effective. I've been using mine for little over three years. I'm going to swap out the Iwasaki for a 20K Helios and if that doesn't make the colors pop either I'm going to upgrade to a higher wattage MH or start mixing in T5's. Covering the tank entirely with all T5's would take away my top down view which I'm hesitant to give up. Tanks running T5's like Iwan Lassers do make me take notice though. Why must I be so fickle? :twitch: