In my introduction to saltwater aquarium lighting, in Chapter 1 I talked about the requirements for lighting a fish-only tank. At the end I began discussing reef aquaria lighting, and provided an outline of the basic types of lighting methods that can be used on a reef system. Since the bulk of reef hobbyists begin with recycled freshwater or introductory marine equipment, I'll first explain the basic fundamentals of fluorescent tubes so you can better understand how they function, and what purposes the various types serve. By understanding these important factors about fluorescent tubes, you will better understand how they will relate to reef lighting as we proceed. Once more allow me to explain that I will undoubtedly ruffle feathers. Occupational hazard, let's move on.
Interestingly enough, I have encountered far more hobbyists that are focused on the hardware more so than the actual animals that all the fancy nomenclature is designed to support. I will not get into the, "what's the best lighting - who's makes the best bulbs", etc., etc., etc. However, what I will do is point out which types of tubes/bulbs/lamps are best for varying conditions or targeted environments. This, is the reason for their ultimate being!
In defense of those folks that want "the best or latest", I applaud your conscience effort to afford your wet-pets with the finest that your money can buy. You may see that you can accomplish similar results spending far less than normally expected. Maybe not as sexy, but definitely effective.
Essentially, fluorescent tubes are the most practical and most cost effective of any lighting source. They burn relatively cool and last many months. What one must watch for when choosing these tubes are their wattage, and CRI (Color Rendition Index), also referred to as "K" (Kelvin). Let's begin with wattage.