Over the last couple months, I have done a little research as I have been disappointed with my Acropora coloring in my tank and all the basic parameters are inline. It appears my Nova Extreme Pro T5 18w lighting system is too bright for my tank set up. Based on information I have read, it is argued adjusting the photo period will improve the aesthetic coloring. Decreasing the photo period is suppose to improve the coral’s colors and growth. I wanted to test this theory for color improvement with my tank.

The Plan

Decrease the photo period initially for my system for the daylights from eight hours to six hours and actinic from ten hours to eight. Decrease photo period further if initial decrease has minimal impact. Will observe several acro corals to access color changes.

The Goal

Improved color for corals

• Red Planet Acro — Vibrant reds return with green baseline
• Roscoes Acro — More blue versus green
• Blue Tip Tenuous — Blue tips return
• Hawkins Acro — Blueish green color returns

The Hypothesis

Decreasing the photo period decreases the growth of symbiotic zooxanthellate algae which can hide the corals underlining pigmentation. Zooxanthellate algae form a symbiotic relationship with corals as they are photosynthetic and provide additional energy to the coral. By decreasing their growth through decreasing the photo period, the colors will improve.

Observations and Information

• 05/04/2009 — Adjusted photo period from eight hours to six hours
• 05/09/2009 — Ended experiment after attending a seminar about clams and their need for a lot of light. An expert advised that clams can not be grown successfully under T5s but need to be grown under metal halides. Based on this information, ending experiment as I run T5s and do not want to compromise my two clams any further besides being under less than recommended lights.

Conclusion

Prematurely ended experiment based concerns for clams health.

So not to be disappointed, I ran across a great article over at Advanced Aquarist’s Online Magazine:
A Different Look at Lighting: Effects of Prolonged Photoperiod, Spectral Quality, and Light Dosage

DISCLAIMER: Your results may very as each system is very different from another. For my tank parameters and environment, this was my observations and conclusion. This was not a controlled experiment so there is a potential for a very large margin of error.

References

Calfo, Anthony. “Thoughts on Reef Aquarium Lighting… Keep your Eye on the Price!” Reefkeeping Magazine. August 2008. Reefkeeping. http://www.reefkeeping.com/issues/2004-08/ac/feature/index.php. Accessed 05 May 2009.

Fatherree, James. Giant Clams in the Sea and the Aquarium. Liquid Medium, 2006.

Fatherree, James. “Reef Aquarium Lighting: How Much Light is Enough?” Liquid Medium Marine Aquarist’s Magazine. June 2008. Liquid Medium. http://www.liquid-medium.com/1_1/how_much_light.htm. Accessed 08 May 2009.

O. Levya, Y. Achituva, Y.Z. Yacobib, N. Stamblera, and Z. Dubinsky. “The impact of spectral composition and light periodicity on the activity of two antioxidant enzymes (SOD and CAT) in the coral Favia favus.” Journal of Experimental Marine Biology and Ecology. Volume 328, Issue 1, 10 January 2006, Pages 35-46. Science Direct. http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T8F-4GTW00N-2…. Accessed 05 May 2009.

Murphy, Tom. “Reefkeeping 101 – Ho! Ho! Ho! – Let’s Light ‘em Up!” Reefkeeping Magazine. December 2007. Reefkeeping. http://www.reefkeeping.com/issues/2007-12/newbie/index.php. Accessed 05 May 2009.

Riddle, Dana. “A Different Look at Lighting: Effects of Prolonged Photoperiod, Spectral Quality, and Light Dosage.” Advanced Aquarist’s Online Magazine. May 20009. Reefs.org Publications. http://www.advancedaquarist.com/2009/5/aafeature. Accessed on 26 November 2009.

Tyree, Steve. “CORAL RHYTHMS AND CAPTIVE SPAWNING.” The Breeder’s Registry newsletter. Volume 1, Number 3, Summer 1993. The Journal of MaquaCulture. http://www.breedersregistry.org/Articles/v1_n3_tyree/tyree.htm. Accessed 05 May 2009.

No related posts.