Marineland LED Aquarium Lights have a double bright row of 6K LED Daylight bulbs and a single center row of 60mw Blue LED's. This has a similar light intensity of a twin tube strip light but uses less energy. Marineland LED Double Bright Lights are good for Fish Only marine tanks or Freshwater low light planted tanks (crypts, anubis, java fern etc). It could also be an excellent light for a refugium system but is not intended as a reef lighting system. The LEDs provide better color rendering, and the natural shimmer effect is likes ones found in much more expensive halide light systems. Each LED is rated one watt and produces 80 lumens of output. There are three LED aquarium light models: an 18"L with 9 LEDs, a 24"L with 12 LEDs, a 36"L with 24 LEDs and a 48"L with 36 LEDs. This LED fixture has a very low profile design, about 3/4" Tall and 5" Wide. Both ends of the light have extendable wire leg supports that allow the three fixtures to expand to fit 24", 36", 48" and 60"L tanks, respectively. The legs can also be totally removed so the light can be placed directly on a glass canopy for an even lower profile. This double bright LED light has a single power cord and a single switch that allows either ALL LEDs ON, just the ACTINIC LEDs ON (for simulated moonlight), or OFF. The LEDs are designed to last 17,000 hours to the point where they are 70% as bright as they were when turned on for the first time. Under normal operation, this means over 5 years of lighting your tank before the light should be replaced, saving replacement cost for bulbs of around $340.