Aquarium Light Bulbs
Aquarium light bulbs are markedly different from the other light sources that are used in your home. While normal household bulbs do not attempted to recreate natural sunlight, those that are made for aquarium usage are meant to replace natural light altogether for your fish. Fish and other creatures you would keep in an aquarium need natural or natural-like light in order to grow healthily just like any other organism. However, not all light bulbs made for fish habitats are the same and some have very specific uses. So it is important to know what you are planning to raise in an aquarium before investing in any light sources.
Pinpointing the natural habitat of any fish or other organisms you intend to keep is the first step to finding proper lighting. For instance, those that come from tropical, bright areas should have bright lighting that is similar to what they would have in the wild. Similarly, any breeds that come from more dark or freshwater areas are not going to need any intense amount of light -- though they will need an appropriate amount. Finally, deep water fish or organisms such as anemones need special lighting to recreate their natural homes.
Proper lighting promotes happy, healthy organisms. There are several types of aquarium light bulbs on store shelves, with each kind being best for different artificial water habitats. You will most commonly find incandescent, halogen, and normal to very high fluorescent. A more advanced type is metal halide, which is great for fish or other organisms that need very high light.
Going with a bulb type that is not meant for the organisms that you are keeping and raising can stunt their growth and cause them to have irregular spawning cycles and sleep patterns. Incandescent bulbs, for example, are best for fish that do not require a great deal of light. The same can be said for halogen bulbs. Normal output fluorescent aquarium light bulbs are best in small tanks made for freshwater fish exclusively. However, high to very high output fluorescent bulbs are more picky: freshwater exclusively if there are plants in the tank, saltwater if there are only fish. This can be hard to remember, but the differences between fluorescent lights are crucial to keeping care of underwater organisms.
Also remember not to leave the light on 24 hours a day. In their natural habitat, no animal sees full sunlight all day. Cycling in 12 hour periods will ensure that they will have as close to normal lives as possible within the aquarium. If possible, get a light dimmer so you can simulate moonlight as well as sunlight at different periods of a day's 24-hour cycle. Utilizing aquarium light bulbs in this way will make your fish feel right at home in their simulated environment.