Keeping Your Fish Alive And Happy

(by Jennifer Carroll March 14, 2001)

There's a lot to remember when you're setting up an aquarium, but it's not really hard if you have the information you need to be successful. Here are some basics for setting up and maintaining a successful aquarium. These aren't all hard and fast rules--there is an art to fish keeping as well as some science--but this is a good place to start and will help you to keep your fish happy and healthy.

Choosing a Tank

• When choosing the size of your tank, keep in mind that a freshwater tropical aquarium should have a minimum of 1 gallon of water for every inch of small fish (bigger fish need even more than that!). Cold-water fish, such as goldfish, need 2 gallons of water per inch of fish. So choose a size that will allow you to have the number of fish that you want.
• If there's a certain type of fish that you want, make sure the tank you choose will meet its needs.
• Fish swim horizontally, so a long tank is usually better than a tall one.
• A larger tank is easier to maintain than a small one and it holds more fish. 20-30 gallons is a good starter size.
• Be careful to choose suitable decorations for your fish. Territorial fish such as cichlids need a lot of hiding places and room to set up territories. Any fish will benefit from the sense of security provided by an aquarium background, plants, and other places to hide when they feel threatened.
• Dark aquarium gravel will help bring out the colors of your fish.

Setting up your tank

• Make sure your tank is set up and running properly for a few days before you add any fish.
• Choose a location for your tank. Placing your tank against an inside wall and out of direct sunlight will help keep the temperature stable and cut down on algae growth. Keeping your tank out of high traffic areas can help keep stress levels down.
• Make sure the surface on which you will place the aquarium is level. Water weighs about 8 lbs. per gallon so make sure your stand can support the weight. A lack of proper support can cause an aquarium to break.?
• Rinse the gravel, carbon cartridges, and other equipment in plain water before putting them in the tank. Carefully follow the instructions for setting up the heater and filtration system.
• Place the thermometer midway up the tank and away from the heater.
• You may need to remove or cut the plastic strip on the back of the aquarium to allow for equipment that is mounted on the back, such as heaters and back filters. Fish can jump out so keep as much of the top covered as possible
• Fill the tank with tap water and use a water conditioner to remove the chlorine and other harmful chemicals.
• It is important that your aquarium maintain a stable temperature of about 78 degrees for most fish before any fish are added. Coldwater fish are comfortable at room temperature and do not require a heater.

Choosing your fish

• Choose fish that are the appropriate size and temperament for the tank you have. Some fish grow quite large and others need a lot of swimming room.
• Make sure that the fish you choose get along with each other and are of compatible sizes.
• Choose a good mixture of top, middle, and bottom feeders.
• Find out about any special needs your fish might have.
• Take the life span, adult size, and growth rate of your fish into account.
• Make sure the fish you choose are healthy.

The Nitrogen Cycle

• Fish release ammonia into the aquarium water through their gills, waste, and uneaten food. This ammonia is very toxic to the fish and is a leading cause of death. Fortunately, there are good bacteria that colonize the tank and convert the ammonia into nitrite, which is also toxic to the fish. Other bacteria convert the nitrite to nitrate, which is relatively safe for the fish.
• Every time you add a fish to your aquarium it releases more ammonia into the aquarium than your current population of bacteria can handle. It takes time for more bacteria develop to take care of the increased ammonia levels. If ammonia levels rise too quickly, the bacteria may not be able to keep up and your fish may quickly die of ammonia poisoning or be more vulnerable to other diseases, so only add a few fish to your aquarium at a time and be careful not to overfeed them.
• When you are starting a new aquarium, add fish very slowly- just one or two at a time. Be especially careful during the first six weeks. Test your water before you add a new fish-- new fish are more likely to die in toxic waters than fish that are already established in the aquarium.
• You can get bacteria starters that will seed the aquarium with bacteria and help the biological filtration process get started, but this doesn't replace the need to be patient and add fish slowly. It still takes time.

Adding New Fish

• When you add your fish, float the bag in your tank for about 15 minutes so that your fish is not shocked by a drastic temperature change.
• Watch to be sure that your other fish don't pick on the newcomer. Fish are curious and may come close to investigate, but watch out for biting or other signs of aggression.
• Being moved to a new tank puts the fish under a lot of stress. Adding a protective slime can help beef up the fish's disease resistance.
• Sometimes adding food to the tank when you release a new fish can draw attention away from the newcomer and give him a few minutes to settle in.

Maintenance

• Regular maintenance is essential to your fish's health. I recommend cleaning your tank once every two weeks. Cleaning your tank shouldn't take very long at all. Here's what to do:
• Decide what day you want to clean your tank. It is easier to remember if you have a regular schedule.
• The day before you clean, wipe down the inside walls of the aquarium with an algae scrubber that is appropriate for your aquarium (some will scratch acrylic surfaces). Even if you don't see algae yet, it is forming and regular cleaning will help keep it from growing. Doing this the day before permits debris to settle to the bottom of the tank to be cleaned out when you vacuum. You can do it all on the same day if you prefer.
• Turn off the filter and heater and allow the heater time to cool off (about 15 minutes) before you remove any water. Use a gravel vacuum to remove the debris from the top 1/2" of the gravel. The gravel vacuum allows you to clean the gravel without disturbing the good bacteria that live in it. Remove about 25% of the water when you vacuum (removing too much at once can be harmful to the fish). This is a good time to clean or rearrange plants and decorations. Fill the tank with clean, dechlorinated tap water. The water you use should be about the same temperature as the water in your tank. Restart your filtration and allow time for the heater to adjust to any temperature changes before you plug it back in.
• If you have a power filter, the cartridges should be replaced every 3-5 weeks.
• Charcoal should to be replaced every 4-6 weeks.
• Airstones need to be cleaned or replaced every 4-6 weeks to keep the pump functioning properly.
• Check the temperature in your aquarium at least once a week. Slowly make any needed adjustments.

Health

• The best way to keep your fish healthy is to prevent disease in the first place. Make sure the environment you provide is safe and stable.
• Follow a regular maintenance routine to keep their water clean.
• Take a few minutes when you feed your fish. Make sure that they are all eating and check them for signs of disease such as discoloration, unusual growths, and changes in behavior. The earlier you catch a problem the easier it is to cure.
• A little aquarium salt can be helpful for some fish, especially mollies. The recommended dosage is 1 tablespoon to 5 gallons of water.
• Never use soap or other household chemicals where they can come in contact with the aquaruim water or for cleaning your tank.
• Objects brought in from the great outdoors can be hazardous in your aquarium. Make sure if you choose to do this that you know what you are doing.

Common Illnesses

• Ammonia poisoning is a common cause of death, especially in a new tank. Rapid breathing and gasping at the surface of the water are early signs that there may be an ammonia problem. Test your water immediately. Partial water changes, zeolite chips, and ammonia detoxifiers can help in a crisis, but it is much better to prevent high ammonia levels in the first place (see The Nitrogen Cycle).
• Ick is an external parasite that is always present in the aquarium and attacks the fish when they are weakened in some way. It often occurs due to poor water conditions or as a result of adding new fish to the tank. All of the fish, not just the new one, can be put under stress and weakened enough for the parasite to attack. Ick looks very much like a crystal of salt. If not treated quickly, more of these parasites will attack the fish until it eventually dies.
• There are several other diseases, many of which can be treated if caught early on. Watch for signs such as abnormal growths, patches of white or yellowish discoloration (variations in color are normal and caused by things such as stress and breeding), cloudy patches, bloody patches, and fluffy scales, and behavior such as scratching, sitting in the water flow, resting on the bottom, lethargy and loss of appetite. These are signs of a possible illness.

Treatment

• There are many medications available to treat fish diseases. Talk to someone who can give you an accurate diagnosis and help in determining how to care for a sick fish.

 The very basics:

• Consider both your needs and those of the fish when choosing an aquarium.
• Run your tank for a few days before adding any fish.
• Make sure your fish are compatible with each other and with the size of aquarium you have and that you can provide for their needs.
• Don't overcrowd your tank or add too many fish at once!
• Clean your tank once every two weeks.
• Watch your fish daily to make sure they eat and check them for signs of disease.

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