LED lights, unlike fluorescents and halides, are cooler and more energy-efficient, and have a longer lifespan. While they tend to be much more expensive (usually several hundred to a couple of thousand dollars) the cost is well worth it when you consider how much use you'll get out of them. Many LED lights can be hung over the aquarium with a simple wall fixture. But if you'd like the lights to be closer to your aquarium without running the risk of having them damaged by water, you can attach them to the outside of your aquarium at the top and angle the light inward.
Choose the necessary colour and brightness of your LED lights. Most fish aren't too particular about the colour spectrum, but you'll want to know the specific needs of your fish. Planted aquariums usually require brighter light for the health of the plants, while non-planted aquariums are better with dimmer light to keep excess algae growth at a minimum.
Determine the number of LED lights you need. The size of your aquarium will impact this choice, so have your aquarium's measurements on hand when you go to pick out your lights.
Choose thin LED rods since you'll be fastening them to the outside of your aquarium.
Stick the suction cups (with the bulb clips sticking out) to the outer top of your aquarium in a straight line. Three, four or five suction cups may be necessary to provide your lights proper support. You can attach your lights to the back, sides, front or any combination of these positions depending on how much light your aquarium needs.
Fasten LED lights to the bulb clips on the suction cups.
Secure the end caps in place.
To keep a regular lighting schedule for your fish, consider using a plug-in timer for your lights. Fish are the healthiest when they receive proper amounts of light and darkness, and a timer can ensure that your lights will stay in routine when you may not be available to regulate your aquarium.