The rule of thumb ing placing light is each light is most effective in a 24 x 24 area underneath the tank. Your tank is 72 in across. SO my recommendation would go with 3 bulbs. Now the wattage is going to be up to you. I presonally went with a 250w Metal halide due to my tank being 24 in wide. The main reason I went with the 250W is the power consumption between the 2 bulbs versus the intensity of the light. I haven't come across a coral that I needed a 400W system yet. the 250W would preform excellent but the 400W would provide a faster growth rate. Also you have to take into consideration that the color specturm of the bulb will also affect the coloration of the corals. The "bluer" you get, meaning the higher up the kelvin scale you go, the slower the corals grow but the more colorful the will get. Real sunlight is at a 6500 Kelvin range. But that will look yellow to our eyes. A bluer hue will more appealing to our census. I've used a 14,000K bulb and 10,000K bulb and now am using a 20,000K bulb. With the 10 and 14000 K bulbs I felt I had to augmentate the bulb with actinic bulbs. With this 20,000K bulb I feel that I don't have too. But we shall see as it's only been on for 1 day so far. Also with the depth issue of you tank either bulb would work with it. If you had a 26 In tall tank I would've said go with the 400s if you wanted corals to the bottom of the tank. But the depth of your tank will allow you to use either system and get good results.
__________________
Photo anyone? 
|
Threaded Mode
