How to Use Hoods and Lighting in Aquarium


The combination of electricity and water is clearly a potentially hazardous one, so any electrical equipment you use for the tank must be specifically designed for aquarium use. It is also essential to include a barrier at the top of the tank, where condensation and lighting would otherwise come into contact. This can be achieved by fitting a condensation tray – usually just a sheet of plastic or cover glass supported on the glass shelves about 1cm below the rim. This cover also serves to prevent any fish from leaping out of the water, but a proper hood with a light is equally essential, particularly if the aquarium includes living plants.

Why lighting is necessary

Lighting the aquarium has two main functions. Providing the right sort of light (from the correct part of the spectrum – like natural daylight) enables plants to photosynthesize and maintain healthy water conditions for the fish; without it, the plants will die rapidly, polluting the tank.

Lighting also illuminates the occupants, especially worthwhile for vivid types such as cardinal tetras, adding greatly to overall effect. Special fluorescent strip lights are generally used for most freshwater aquaria since their heat output is minimal and does not disrupt the stability of the water temperature; ordinary fluorescent tubes are unsuitable because the light output is from the wrong part of the spectrum.

Lighting checkpoints

  • Use lighting tubes that are purpose designed for aquaria. They emit light from the red and blue parts of the spectrum, similar to natural sunlight.
  • Tubes are sold in a range of lengths. If necessary, depending on the fitments in the hood, you may run two tubes in parallel.
  • Remember, the level of illumination needed is partly affected by the location of the tank and its depth. As a guide, allow roughly 10 watts (W) of fluorescent light for every 30cm (12in) of tank length.
  • Make sure the lighting runs the whole length of the aquarium, to provide even illumination in the tank.
  • It is usually recommended to light the tank for eight to ten hours a day. You can use a timer switch to control them automatically if you prefer, provided that the control unit can operate fluorescent lighting (many timers are for incandescent lights only).
  • Beware of overlighting: this tends to trigger excessive algal growth within the aquarium, although this will not be immediately apparent. If you do notice this becoming a problem, one way to counteract it is to reduce the time that the aquarium is lit each day.

Incorporating the lights

At the rear of the hood, there is space to accommodate the light fitments, with the tube itself being fitted between special connectors, which are designed to exclude damp. The pins on the tube serve to anchor it in place here; make sure they do not become bent or otherwise damaged, or the light may not work.

To fit the tube correctly into the hood, anchor it firmly in place using the plastic clips, which should be located close to the ends. Whether the control unit is inside or outside the hood, there should be easy access to the lighting switch. Keep any excess cable tied up in the hood; you might need it, if you move the aquarium to a new position at a later stage.

Subdued lighting

Bright lighting is not always desirable, especially if you want to watch fish that normally live in darkened surroundings. It may be better to opt for plastic plants and a lower wattage output, so as to replicate the light levels in the fish’s natural habitat more closely. This applies in the case of blind cave fish (Astyanax fasciatus mexicanus), for example, as well as various catfish.

Another means of screening the water and diffusing the light is to incorporate floating plants. In this case, make sure that the tank is not filled up to the maximum level or the plants may come into contact with the condensation tray or cover glass. The water here is almost bound to wedge the plants to some extent, and before long, in spite of the bright light, they may well start to rot. As a precaution, allow a gap of about 15cm (6in) from the rim. The currents in the aquarium tend to wash floating plants into a corner, especially if you use a power filter. Provided that there is an adequate circulation of air, however, they should remain healthy.

Lighting plants above water

If you are especially interested in aquatic plants, you might consider a more specialist arrangement – certain tropical plants naturally occur close to the water and these may be attached instead to the back of the aquarium, above the water line. This means you necessarily have to allow a much bigger gap between the lights and the water beneath, which also enables aquatic plants that would normally grow up and out of the water to thrive in this kind of set-up.

Unfortunately, this is rarely possible in a typical aquarium, where a relatively large number of fish are housed together, because the reduced volume of water limits the stocking density. If you have the space for a large tank, however, an established aquarium of this type can be immensely striking. You may need an aquarium specially designed for this purpose, and you are also likely to require more powerful lights, for the benefit of any plants that grow actually in the water.

Further Readings:

Filed Under: Pets & Animals

Tags:

About the Author: Fred Goodson has a passion for pets and animals. He has 4 dogs and is planning to have another one. He is also a blogger who writes about pets and animals. Currently, he is living in New Jersey.

RSSComments (0)

Trackback URL

Comments are closed.