Introduction to Home Aquariums
Aquariums are popular decorative features in homes, offices, and even restaurants. They can be beautiful facsimiles of exotic underwater environments, such as the Amazon River or the Great Barrier Reef. And besides being fascinating to look at, aquariums provide a tranquilizing element in a world filled with stress. But before you decide to add an aquarium to your home or office, you should learn as much as possible about their care and maintenance.
Most people who have aquariums--or aquarists, as they are known--keep tropical (warm-water) fish, such as angelfish, rather than cold-water fish, such as goldfish. That is because tropicals are generally more colorful and exotic-looking than cold-water fish.
There are two basic types of tropical fish aquariums, freshwater and saltwater. Most experts advise against starting with a saltwater aquarium, because it is more expensive to set up and stock and more difficult to care for than a freshwater aquarium. If you begin with a freshwater aquarium, you can use most of the same equipment later if you decide to switch to a saltwater setup.
The first thing to consider is the size of the aquarium you want. If you are trying to fill a specific location in your home, you will have to buy what fits best in that spot. To get some advance idea of the size aquarium you need, keep in mind that one of the most common 76-liter (20-gallon) rectangular tanks has proportions of about 60 centimeters long by 30 centimeters wide by 40 centimeters high (24 x 12 x 16 inches).
If space is not an issue, buy the biggest tank you can afford--at least 76 liters. You may be tempted by inexpensive 38-liter (10-gallon) starter aquariums available in many pet stores. But these usually come with inferior equipment and do not offer enough room for even a small number of fish, and certainly not for the variety of fish you are likely to want.
When selecting a tank, keep in mind that the larger it is, the heavier it will be when it is full and operating. A liter (0.26 gallon) of water weighs 1 kilogram (2.2 pounds). So, a 76-liter aquarium, once filled, weighs more than 76 kilograms (170 pounds), counting its own weight and the weight of anything in it heavier than water. It is important to consider such great weights when deciding where to place your aquarium. You might want to buy a special stand for it. Some stands are made of black wrought iron, and others are specially constructed wood cabinets.
Glass or Plexiglass?
The next consideration in selecting an aquarium is whether to buy a glass tank or one made of plexiglass, a strong plastic material. Because of the great transparency of plexiglass, a tank made of this material can actually look clearer than a glass tank. In addition, a plexiglass tank is usually constructed so that the front face curves gracefully backward at the corners to form the sides of the aquarium. This design thus eliminates the sharp vertical lines of a glass aquarium, in which the front panel meets the sides. With the absence of edges, a plexiglass aquarium looks more like a magical block of water than a container holding water.
Plexiglass also has other advantages. It is much lighter than glass, it maintains water temperature better than glass, and it is virtually unbreakable. On the other hand, a plexiglass tank is more expensive than one made of glass. A typical 76-liter glass tank costs $25 to $35, while a similar-size plexiglass tank can cost twice as much. Plexiglass also scratches more easily than glass, so an aquarium owner must take extra care when cleaning the tank or adjusting the contents of the aquarium.
When you have finally chosen a tank and brought it home, be sure to find an appropriate place for it. One consideration is the amount of natural light that the aquarium will get. It surprises many novice aquarists that window light--especially direct sunlight--can be a great menace to an aquarium. Too much light can promote the growth of algae in the tank, turning the water green. It can also raise the water temperature to levels that kill the fish. In addition, streams of hot or cold air can affect water temperature, so protect your aquarium from winter drafts and avoid placing it near open heating and air-conditioning vents.
Heaters and Filters
Having set up your tank on a strong base and in a good location, you are ready to fit it out. The basic equipment for an aquarium includes a cover or hood for the tank, a heater, a filter, a light source, a thermometer, and various decorative items, such as gravel, plants, and rocks.
A heater is an essential element of an aquarium because you will probably be keeping tropical fish that require constant water temperatures of 24 to 27 degrees C (76 to 80 degrees F). Aquarium heaters are rated in watts of power. Figure on 1.3 watts of power for each liter of water in an aquarium (5 watts per gallon). So, for example, a 76-liter tank requires a 100-watt heater.
Aquarium heaters are adjustable and controlled by a thermostat. The thermostat and heating element are enclosed in a long glass tube that either hangs into the water from the side of the tank or is fully submerged in the water.
A filter is another important piece of equipment for your aquarium. The best filters perform both mechanical filtration to remove particles and chemical filtration to remove harmful chemicals resulting from the body wastes excreted by the fish. Filters also accelerate the exchange of oxygen for carbon dioxide (released when fish breathe) at the water's surface.
Many experts believe that the best of the new filters are those that hang on the outside-back of the tank. These filters take water in from a tube that hangs in the tank, pass it through a fiber mesh to filter out particles, then pass all or some of the water over a revolving wheel. The water then returns to the aquarium across a broad lip that creates a sort of small waterfall just above the surface of the water in the tank.
The entire filter, and in particular the wheel, becomes inhabited by beneficial bacteria that occur naturally under water. These microbes break down the deadly ammonia and nitrites that form in an aquarium and convert them into relatively harmless compounds called nitrates. And the water's trip in a relatively thin sheet over the spinning wheel and through the waterfall maximizes the exchange of carbon dioxide for oxygen.
Other Equipment
The best kind of light source for your aquarium is one that is built into the hood or cover that fits over the top of the tank. A hood is needed to keep fish from jumping out of the tank and to prevent cats and dust from getting in. It also minimizes evaporation and heat loss from the tank.
Although most aquarium hoods are equipped with fluorescent lights, there are now many kinds of high-output bulbs available to aquarists. The new bulbs provide brighter light with spectrums that aid plant or coral growth and intensify the colors of the fish.
Aquarists also have different kinds of thermometers to choose from. One of the most convenient to use has flat magnets mounted on its ends. It is placed against an inside surface of the aquarium and is held in place by another set of magnets on the outside of the tank. Sliding the outside magnets causes the inside magnets to move the thermometer, a feature that is particularly useful when you are cleaning the inside of the tank.
Aquarium gravel comes in many colors. Most aquarists prefer natural colors, but some like to use brightly colored gravel that you would never see in nature. When making your own selection, just remember that you want the fish to be the main attraction, not the gravel.
The rocks and plants for your aquarium should come from a pet shop, not from a streambed or a vacant lot. The wrong types of rocks can cause changes in the chemical composition of the water that are harmful to the fish. The wrong kinds of plants can introduce diseases and foul your aquarium water. Many aquarists avoid real plants altogether and decorate their tanks with plastic plants. These artificial plants are remarkably lifelike and make an excellent substitute for natural vegetation.
Selecting Your Fish
Stocking your aquarium should be a gradual process. It is best to add only a few fish at a time to avoid overstocking the tank and jeopardizing the health of the fish. No hard and fast rules exist about how many fish you can put in your tank for a given volume of water, but it is better to be understocked than overstocked. A rough estimate is 2.5 centimeters (1 inch) of fish body length per gallon of water, meaning you can put about ten 5-centimeter (2-inch) fish in a 20-gallon tank. This number, however, can be safely doubled to 2 inches per gallon in a well-filtered and well-aerated tank.
Most aquarists start with a so-called community tank, which is a mixture of compatible fish selected without much regard to what parts of the world they come from. There are a few basic rules for picking such a mixture. You should consider the behaviors of the species you will mix, such as their aggressiveness or sense of territory; the level of the tank at which the fish eat (top, middle, or bottom); the size each type of fish may reach as it matures; and the chemical composition of the water you will be using. A knowledgeable pet-store employee can help you pick the right mix of fish for your aquarium and tell you how to introduce them to your tank.
Things to Watch Out For
Once you have your aquarium up and running, there are several potential problems and hazards you should look out for:
Overfeeding the fish. The number-one reason new aquarium owners fail is that they give their fish too much to eat. Excess food can foul the water and harm the fish. Feed your fish no more than they will eat in five minutes. And be sure they are actually eating the food rather than simply taking it in their mouths and then spitting it out.
Incorrect water temperature. Because fish are so sensitive to changes in water temperature, it is advisable to check the aquarium thermometer every day to make sure your water heater is functioning properly.
Fish diseases. Fish can get sick just as people do, so look at your fish carefully every day, especially for a few weeks after you add new ones to the tank. The most common disease affecting tropical fish results from an infection by a parasite called Ichthyophthirius multifiliis, abbreviated as Ick or Ich. This disease can wipe out an entire tankful of fish. The tiny Ich organism multiplies quickly and has a spore stage that can be seen on your fish as tiny white spots that look like salt. You can knock this disease out fast by placing medications containing quinine and malachite green into the water.
Electric shock. Electricity and water are a hazardous combination. To avoid the possibility of getting a shock, do not touch your electrical equipment when you are wet, unless it is unplugged.
Skin irritations. If you have your hands and arms in the aquarium a lot, you may find that they start to feel dry and itchy, and you may even develop a rash. If this problem occurs, the best solution is to buy a pair of elbow-length waterproof gloves to protect your skin from the water.
Many aquarists become so interested in one aspect or another of their aquariums that they begin to keep specialized varieties of fish. Some concentrate on one type of fish, such as angelfish or guppies. Others specialize in fish from specific locations, such as South America or Africa. Some aquarists even begin to breed their fish.
If you become interested in this approach to owning an aquarium, you can find specialized equipment and other aids at most pet stores. Among the newest aids are sophisticated chemical water supplements that have only recently become available to amateur aquarists. Sold under trademarked names like Instant Amazon and Rift Lake Vital, the supplements alter your aquarium's water chemistry to closely resemble that of the waters from which specific kinds of fish come.
Setting up a home aquarium can be a complicated and expensive venture. But the rewards can be priceless in terms of adding beauty and tranquility to your personal environment.