How many watts per individual bulb/light point? The trend is toward higher wattage to provide more shimmer and shadows similar to the sun or at least MHL. Current mass produced LED fixtures with multiple points of light look eerie and clinical/fake like fluorescent light.
What are the dimensions of the fixtures? It seems tall 20.5"? Usually LED's are low profile 3"ish.
There are no known negative aspects to a lack of UV, or conversely benefits to having it, but in my unpopular opinion natural conditions should be replicated and UV does readily exist on natural reefs. Corals develop UV protection (mycosporine-like amino acids/MAA's) as sun block from the harmful UV rays of the sun. Reef fish have these same MAA's in their mucous. These were originally believed to be pigmented but are now known to be colourless. The zooxanthellae (symbiotic algae) within the coral's tissue are a light brown or drab green colour and do not require UV to our collective knowledge. This article and the series by Dana Riddle covers the subject of lighting and coral colouration.
http://www.advancedaquarist.com/2009/1/aafeature1
PAR is the biggest single lighting parameter you need to monitor. It will indicate if your bulbs are old and if they are adequate in the first place. PAR is basically the quality and intensity of light that is required for photosynthesis. LUX is the intensity reading that includes the higher nanometer (nm) light that is easily recognized by the human eye as being "bright". These readings are good for testing bulb life but do not indicate the hidden PAR generated by the light.
The other consideration is coverage, as LED tends to cover a smaller spotlight area compared to MHL or natural sunlight. Home & office use LED lamps are starting to use 7 watt multichip LED clusters.
http://shop.humanscale.com/family.cfm?groupid=87 and there are even 100 watt LEDs used in the aquarium trade now.
http://econlux.de/2010/
Your tank is shallow so lighting is not as challenging with regard to penetration, diffusion and intensity.
There are two ways of looking at the lighting issue. One way is to find out what corals appear to require for growth, health and colouration, then create those conditions with the technology available to us. The second approach is to match the lighting conditions of natural reefs and assume that nature got the formula and balance right and we can't improve upon it. It's a matter of personal choice just like GMO's (genetically modified organisms) or organic foods.
Enjoy the reading & research
what are you planning on for your frag tank, and cutting board/fraging station?? you will be needing one, i didn't think id enjoy fragging but now its almost a obsession in a good way of coarse :]
:bounce1::bounce2:
