With so many options to choose from, it can be difficult to select the best aquarium light bulb for your aquarium. We’ve narrowed it down to what we think are the top performers in each category.

Power Compact Aquarium Light Bulb

If you need to replace your power compact aquarium light bulb, which you should do every six months, then the first step is to determine whether you have straight pin or square pin bulbs. This can be done by removing the bulb from its endcap. Straight pin bulbs have four pins in a row, whereas square pin bulbs have four pins in a two by two square. Then check the wattage, the most common wattages are 55 watts, 65 watts and 96 watts. There really isn’t a big difference in performance between the different power compact bulbs, so you should really focus on color. Many aquarists prefer one daylight bulb and one actinic bulb. Those that like it a little more blue should try one 50/50 bulb combined with an actinic or 420nm/460nm bulb.

T5 Aquarium Light Bulb

T5 bulbs should be replaced every year. Some of the most popular brands are UVL/IceCap and Giesemann. In my experience IceCap makes both a quality actinic and daylight aquarium light bulb, but Giesemann’s actinics don’t seem to be as bright. Their AquaBlue+ bulb is a nice crisp white. One of the most popular T5 aquarium light bulbs is ATI. It seems that most aquarists like the AquaBlue+ and AquaBlue Special because they are bright and produce a nice blue and white. Most people will like a one to one ratio or three to one ratio of actinic bulbs to daylight bulbs.

Metal Halide Aquarium Light Bulb

Metal Halide bulbs will last between six months and a year with higher kelvin bulbs needing to be replaced more frequently. If you have a single or mogul base bulb the best option is a 10,000K Ushio or a 10,000 XM bulb. If you prefer a more blue look then try a 20,000K XM or a 20,000K Radium. These bulbs are really the industry standard and have been time tested. If you have an HQI or Double Ended bulb you may consider trying the 10,000K Ushio, 10,000K XM, 14,000K Phoenix or the 20,000K XM. One of the biggest contributors to the color of the aquarium light bulb is the ballast. Some ballasts make the bulb run more white, while others will turn it more blue. When shopping for an aquarium light bulb, the best place to start is online because these vendors will usually be half the price of more traditional fish stores.