Aquarium lighting this multi-tier reef system was perhaps the most time consuming, but also the most fun and rewarding from the standpoint of knowledge. Overall, aquarium lighting is a very controversial issue, with a multitude of products the consumer seeking aquarium lighting often finds himself or herself confused. I had some experience with aquarium lighting, but nothing to the scale of this new reef aquarium system.
My 40 gallon reef system was illuminated by six 110w VHO bulbs. Prior to this endeavor I did not have the opportunity to experiment with different lightingcombinations, in fact the aquarium hood I designed and built was my first attempt at aquarium lighting.
I figured this was my chance to try anything I wanted and I welcomed this opportunity. I wanted to try to match the Kelvin temperature over each section of the coral reef in my reef aquarium, so I set out to illuminate them all differently. I wanted different wattage and different Kelvin temperature of the bulbs.
Starting with the lagoon, I ran two 5500k 175w Metal Halide bulbs; ideally they would have been much brighter like 400 watt Metal halides aquarium bulbs. At the shallow depth bright bulbs in the color spectrum would have caused allot of complications with nuisance algae. This forced me to use the 175w metal halides.
The back aquarium reef was one 10k 175w Metal halide; I would have liked to use something a bit bluer and a bit more intense. I went with the 10k, but I most likely should have gone with a 6500k metal halide. The back reef is a shallow area usually pretty flat.
The lower aquarium reef was a 20k 175w Metal halide. I did feel that was fairly accurate and a good choice for the aquarium setup. The upper reef a 14k 175w Metal halide and the aquarium reef crest used 2 175w 6500k Metal Halide bulbs. As time progressed I modified the lighting setup to increase intensity over than aquarium. By dropping the temperature with the chiller and increasing the PH and salinity to a lesser extent, I was able to ward off a large bit of the nuisance algae that would typically be associated with increased intensity over such a shallow reef aquarium system.