In the past, I made DIY LED moonlighting for all of my tanks (the largest being a 65g reef; now I have a 300g, and will probably use a 15W blue incadescent light). LED moonlights are easy to make, and provide a cool effect for the tank after the main lights have gone off. All of my LED setups that I've made have cost less than $10, and require only an hour or two of work.