- 1). Purchase two fluorescent light fixtures, each capable of holding two old-style fluorescent tube lighting. In most cases, these can be ordinary fixtures from the hardware store; you will only need fancy fixtures if you plan to keep the most delicate organisms. The appropriate length of the fixtures depends on your tank size. They should be almost as long as the tank itself, typically 2 to 5 feet. This will ensure that the light in your tank comes from directly overhead, reducing shadow creation and providing a more natural environment for your aquarium critters. Also, make sure the fixtures don't have a covering or have a removable covering, so that the lamps can be directly exposed to the top of the tank.
- 2). Purchase four fluorescent lamp tubes to fit your fixtures. Two of these should be white. There are many shades of white available to you, which will have a different effect on the quality of the light for both the critters in your tank and the humans who observe them. To get the best advice on your particular setup, you may want to buy the lamps at a fish store from a knowledgeable expert. However, plain daylight lamps from the hardware store will also work. The other two lamps should be blue—that's ordinary blue, not ultraviolet. The blue lights boost the appearance of your tank and the health of its inhabitants.
- 3). Install the blue lamps into one fixture, and the white lamps into the other.
- 4). Install a timer on the white light fixture so that it will be lit continuously for 12 hours at a fixed time each day, roughly to coincide with actual day and night in your home. If your fixture allows for independent timer control, install a separate timer for each lamp. Set one to provide 11 hours of light and the other 12 hours, with the extra hour divided into 30 minutes immediately before and after the other lamp is lit. This staggering effect simulates the reduced light levels at morning and evening. If you plan to keep photosynthetic organisms in your tank, you may need to run the lights longer. Consult with an aquarium expert.
- 5). Install a timer on the blue light fixture so that both blue lamps will be lit continuously for one hour longer than the longest-running white lamp. Once again, divide the extra hour of light into 30 minutes immediately before and after the white light is lit. This simulates the twilight effect at dawn and dusk, and is also pleasant to watch at the end of the day. The effect is not merely aesthetic, however. Stress is a major source of death in sea creatures, and abrupt changes in lighting are a significant cause of stress. A gradual transition between total lighting and total darkness will promote a healthier aquarium.
- 6). Place the fixtures over the tank and connect them to power.
- 7). Replace any burned-out lamps immediately. Keep extra lamps on hand for this contingency. Even if they don't burn out, replace your lamps once a year. Fluorescent lamps become less effective over time, and while this can be hard to see with human eye, the creatures in your tank will certainly notice it.
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