The AquaEl Leddy Slim Marine LED Fixtures are appropriate for reef aquariums. The bluish LEDs combine to produce a 10000K light. These thin but powerful lights come with a very well designed light mount that can be adjusted to fit the dimensions of oddly sized tanks. The light is 30 long and the mount can accommodate tanks up to 40 wide. You might consider combining this light with the AquaEl Leddy Slim Actinic LED Light for a more complete reef aquarium appropriate lighting spectrum. - 32W. 10000K. - Appropriate for reef aquariums - Black light body - For tanks from 30 - 40 wide. The mounts slide easily but remain firmly in place.