Aquarium Lights
There are two types of lights commonly used for aquariums: incandescent and fluorescent. Incandescent lights cost less to buy but cost more to operate. Fluorescent lights are cooler and make more efficient use of electricity, so they are less expensive to operate.

Most fish don’t need a light above them in the aquarium. The light in the room is plenty of light for the fish. But many people prefer a lighted aquarium, so they can see the fish better. Saltwater Reef aquariums do need many hours each day of special strong lighting.

Turn the lights off in your freshwater aquarium, when you’re not looking at the aquarium. This will reduce the growth of the algae and green water in your aquarium.

Finally, do not depend on the aquarium lights to heat the aquarium water, instead get an aquarium heater and thermometer.