How to Install Aquarium Lights. Light in your fish tank is required for the creation of both fish and plant energy. Most fish and aquatic vegetation need somewhere between 10 and 12 hours of light each day. Some fish even actually require certain color lights for the spawning process. In order to adequately accommodate both fish and plant needs, aquariums should be fitted with a lighting system. Fortunately, most lights are fairly easy to install.
Make sure the plug to your tank's overhead light hood is unplugged.
Determine the right type of bulb and wattage needed for light hood. Most require fluorescent lights. In general, you will need 2 watts for every gallon of water in your tank if you have plants with low light requirements. If you have dense plant life with high light requirements, you will need about 5 watts per gallon.
Screw in the correct size and wattage bulbs into the hood. Make a note in a visible spot of the date you installed your lights so you can remember to change them out after the right amount of time.
Mount a remote ballast in an area with plenty of ventilation. This is an electrical device to start and regulate the flow of electrical current from the fluorescent lights. The ballast will effectively dissipate the heat from the bulbs.
Install a timer system if desired. A timer will automatically turn on and off the lights at certain intervals. This can be very helpful if are ever gone for a full day and are not able to manually flip the switch for the aquarium lighting. Your aquatic life will also stay healthier and happier if they have consistent light and dark periods.
Install the overhead light hood back on top of the aquarium and be sure it is properly secured.
Plug in the cord and turn on the lights.