Ultimate Secrets To Saltwater Fish

Idiot Guide To The Marine Aquarium

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Think carefully about where the tank will be placed because once the aquarium is set up, it cannot easily be moved.

water. Since most marine tropical fish prefer water warmer than 75 degrees Fahrenheit, the amount of oxygen may be limited in the tank. If a tank has a lot of surface area, which is dictated by its length and width, then it has more room for gas exchange at the surface. This means more oxygen entering the water and more toxic gases leaving the water. Hence, larger tanks can hold more fish.

As you consider the size of your aquarium, think about the number of fish you would like to keep. Most aquarists use fish length and tank volume to estimate the number of fish that a marine aquarium can hold. Larger fish consume more oxygen and therefore require more aquarium space. The general rule is 1 inch (2.5 cm) of fish per 4 gallons (18 liters) of water for the first six months. After this initial period, you can gradually increase fish density to 1 inch per 2 gallons (9 liters) of water. For example, a 40-gallon aquarium should contain no more than 10 inches of fish for the first six months. These may be one 3-inch Queen Angel, two 1-inch Clownfish, one 2-inch Regal Tang, one 1-inch Bicolor Blenny, and two 1-inch Beau Gregories. After six months, additional fish may be added gradually to increase the total number of inches to 20.

Long tanks are much better than tall tanks because surface area is so important to the capacity and health of your aquarium. Even though both tanks may hold the same volume of water, an upright (tall) tank has a much lower carrying capacity of fish because of its smaller surface area. The minimum size starter tank for the saltwater aquarium should be 30 gallons.

Consider the size of your fish when you are stockingyour aquarium. This Ocellated Damselfish will grow to be 4 inches long.

Tank Tips

Here are some basic things to keep in mind when choosing your aquarium tank.

• Choose the largest tank you can afford and accommodate.

• Choose a long, low tank rather than a tall one.

• Never use a Goldfish bowl.

• Choose a tank with no scratches.

• Make sure there are no gaps in the seams.

Once you've decided on the appropriate size of your aquarium, choosing the tank itself is fairly straightforward. For decades, home aquariums were made only of rectangular glass plates sealed with a silicone rubber cement. These were by far the most common and practical aquariums to buy and they are still quite common in the trade. They are built for the sole purpose of housing living animals and are, therefore, nontoxic. They don't easily scratch, either.

In recent years, acrylic aquariums have become very popular for a number of reasons. They are molded and have few seams, making them more transparent. Acrylic is also lighter than glass and is offered in more shapes and sizes than standard glass aquariums. It tends to be stronger than glass, so it will not crack or shatter as easily. However, acrylic tanks do scratch easily and they can be quite a bit more expensive. Algae scrapers and tank decorations will damage the tank when not properly handled.

Whether you choose glass or acrylic depends on your personal preference and your pocketbook. Regardless, make sure there are no scratches and that there are no gaps in any of the seams when you pick out your new tank.

The Aquarium Stand

The best support for the heavy weight of the aquarium and all its components is a commercially manufactured aquarium stand. This specialized piece of furniture is built to hold a full aquarium. Since salt water is very corrosive, a wooden stand tends to last longer than wrought iron.

Homemade stands and common household furniture may look sturdy, but they can fail under the heavy load. Stand failure can be costly to an aquarist and to a homeowner, so don't try to save money on your support for the aquarium.

If you decide not to buy a commercially built stand, cut a 5/a-inch sheet of plywood and a /4-inch sheet of polystyrene to the dimensions of the tank, and place both under the tank. These layers will even out any imperfections in the supporting surface and distribute the load.

The Tank Hood

An essential item for any aquarium is a hood (also called a canopy or cover). This important piece of equipment performs a variety of functions. First, it prevents unwanted items from entering the tank and injuring the fish. Second, it keeps overzealous fish from jumping out of the tank. (Remember, fish cannot breathe air, and nothing is worse than finding your pet on the floor next to the aquarium in the morning.) Third, the cover prevents water from splashing to the walls and floor, causing damage.

Fourth, it slows the rate of water evaporation from the tank. Water will condense on the cover and re-enter the tank instead of evaporating into the room.

An aquarium hood will help keep your fish and your water in the tank, where they belong. This is a Jeweled Tang.

This limits the necessity of adding more water. When water evaporates from a seawater aquarium, the salts do not leave the tank, but instead become more concentrated, thereby increasing the salinity of the water. This will disturb the fish and the water quality if it is not carefully monitored.

Fifth, the hood helps the aquarium retain heat, thereby reducing the use of the heater. And finally, the hood keeps water from damaging the aquarium light and prevents a potentially dangerous electrical problem.

The hood is generally fitted to the dimensions of the tank and can be adjusted to allow for aquarium accessories. Make sure it is made of thick glass or plastic so it can support the weight of other aquarium components, if necessary. Also, it should be segmented so the entire assembly need not be removed to feed the fish or work in the tank.

For the beginner, I strongly recommend the type of hood that also houses the aquarium light. These units are self-contained and designed to keep water away from the lighting unit. I've always felt that the tank, stand, and hood should be built by the same manufacturer and purchased as a package. This ensures the aquarium components are not mismatched, and it also may be less expensive.

The Water

The most important requirement of healthy fish is clean water. Fish in the natural marine environment live in an open system where water quality is generally not a problem. Products of respiration and digestion are readily swept away and naturally filtered. The sheer volume of water keeps these substances at extremely low levels.

In contrast, fish housed in an aquarium live in a closed system where the products of respiration and digestion remain until they are removed. The primary piece of equipment that removes these toxic substances from the aquarium is the filter. Before we discuss filtration and the types of filters available to the aquarist, it is important to examine the attributes of water quality and the natural wastes of fish.

Sea Water

The chemical composition of sea water is consistent throughout the world. Although sea water is 96 percent pure water, it also contains many dissolved minerals. Eighty-five percent of the mineral content is sodium and chlorine, but magnesium, sulphate, calcium, and potassium amount to another 13 percent, and bicarbonate and sixty-eight other elements, in trace quantities, make up the remaining 2 percent.

Water Quality

Marine fish are accustomed to much more stable environmental conditions than their freshwater counterparts. They are very sensitive to even small amounts of toxins and, hence, are more difficult to keep in captivity. Therefore, maintaining excellent water quality is critical. This means monitoring and occasionally adjusting several water parameters, including temperature, pH, oxygen, salinity, and nitrogenous compounds.

The beginner may be inclined to use natural sea water for a home aquarium. However, for several reasons, I strongly recommend that you use one of the synthetic salt mixes that are available at your pet store. First, if you do not live in the tropics, your local sea water is cold water that contains species of plankton that are not adapted to tropical temperatures. Elevating the temperature causes these organisms to die or rapidly proliferate, yielding polluted and poor-quality water. Second, the logistics of traveling back and forth to the seashore for large quantities of water will ultimately render its use impractical. Third, there are no guarantees that your water source is free of pollution. Seemingly clean sea water may contain high levels of toxic compounds and metals. Why take chances?

The science of marine chemistry has yielded salt mixes that mimic sea water without the potential toxins. These mixes can be dissolved in ordinary tap water for the home aquarium. You should always mix up additional salt water for water changes and emergencies. Batches of salt water should be stored in non-metallic containers in a cool, dark place until needed.


Marine species of fish thrive in water that has a very specific level of dissolved salts. Therefore, the amount of dissolved salts, or salinity, in your aquarium water must be measured frequently and maintained at the level that is best for your fish. To directly measure salinity, you need equipment that can be expensive for the average aquarist. Therefore, the easiest and most practical way to measure the salinity in your tank is to measure specific gravity. Technically, specific gravity refers to the ratio of the density of sea water to the density of pure water at various temperatures. Pure water has a specific gravity of 1.000. Water with a specific gravity of 1.021 is 1.021 times denser than pure water.

Use a hydrometer to measure specific gravity in the aquarium. This is an essential piece of equipment for the marine aquarist, and it must be used every couple of days. You can get a floating tube—type hydrometer or a needle type, which is easier to read.

Specific gravity should be in the range of 1.021 and 1.024, but more important, it should be maintained at a very even level within this range. Even minor fluctuations can cause problems for your fish.

The major cause of salinity changes is evaporation from the tank. When water evaporates in a marine aquarium, the salts remain in solution and the water becomes more concentrated, thereby increasing the salinity and the specific gravity. You must constantly monitor water levels in the aquarium to prevent these fluctuations. Evaporation is easily remedied by adding fresh water to the tank—not additional salt water. Don't wait until levels have significantly dropped before you top off the tank. Instead, do so regularly with small quantities from the tap.

There can be some loss of salt from the tank due to crystallization on the hood and other fixtures and losses from the protein skimmer (see page 38). Keep an eye on the hydrometer, but be mindful that water evaporation occurs faster than salt loss.

When we talk about pH, we are really referring to levels of hydrogen ions in solution. Ions are simply atoms with an electrical charge. We measure the number of hydrogen atoms on a pH scale. The pH scale tells us how many hydrogen atoms are in a solution and, therefore, how acidic it is. The lower the number on the scale, the more hydrogen atoms.

The pH scale ranges from 0 to 14; a pH of 7 is neutral, a pH of 1 is very acidic, and a pH of 14 is very alkaline. This scale is logarithmic, meaning that each number is 10 times stronger than the preceding number. For example, a pH of 2 is 10 times more acidic than a pH of 3 and 100 times more acidic than a pH of 4.

Salt water is more alkaline than fresh water. If you had a freshwater aquarium, you probably maintained the pH within the range of 6.5 to 7.5. By contrast, the

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The COMPLETE guide to Aquariums

The COMPLETE guide to Aquariums

The word aquarium originates from the ancient Latin language, aqua meaning water and the suffix rium meaning place or building. Aquariums are beautiful and look good anywhere! Home aquariums are becoming more and more popular, it is a hobby that many people are flocking too and fish shops are on the rise. Fish are generally easy to keep although do they need quite a bit of attention. Puppies and kittens were the typical pet but now fish are becoming more and more frequent in house holds. In recent years fish shops have noticed a great increase in the rise of people wanting to purchase aquariums and fish, the boom has been great for local shops as the fish industry hasnt been such a great industry before now.

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