There are a variety of T5 Bulbs available for your Saltwater Aquarium. Some of the most popular colors are 10,000K White, 420nm Actinic and 460nm Actinic. Most aquarists use a one to one ratio of daylight bulbs to actinic blue bulbs.
T5 Bulbs Reviews
Some hobbyists like their tanks slightly more blue and in this case a one to three ratio of daylight bulbs to actinic blue bulbs is recommended. Daylight bulbs tend to be brighter and can easily offset any blue created by the actinics. Some of the most popular T5 Lighting brands include ATI, Gisemann, UVL and Ice Cap. Each manufacturer has their own take on the different daylight and actinic variations. One of the most popular combinations is a 12,000K daylight bulb combined with two 460nm actinic bulbs and one 420nm actinic bulb. The difference between the 460nm and 420nm bulb is the 460nm cast more blue and is brighter, whereas the 420nm bulb is more purple, but causes more fluorescence in corals.
Now you may be wondering, can I replace the bulb in my normal output fluorescent fixture with a T5 bulb? No, bulbs meant for aquariums are different than bulbs that can be purchased at the hardware store. They also have a higher light output and require a more powerful ballast to light the bulbs.
Here is an image that compares the diameter of the different bulbs. Notice that T5 bulbs require less space, so more bulbs can be placed in a fixture.
T5 Bulbs – Lengths and Wattage
24″ – 24 watts
36″ – 39 watts
48″ – 54 watts
60″ – 80 watts