This is what I have Only 4 months old, this light unit has 23 10,000k white LEDs and 4 royal blue LEDs, and a rocker switch which allows all off, all on, or just blue on. Currently in use over a freshwater tropical tank but could be used for marine to give a huge cost saving over standard t5/t8 tubes. The unit has expanding brackets which will allow it to be used on tanks ranging from 24-36". I have had good plant growth with this, but am positive it would work on both fresh or salt water where a 10,000k light was required.