I'm thinking of getting an aquarium. How can I ensure success?

Welcome to the wonderful world of aquariums. This FAQ provides advice and guidance to help insure success in your endeavor. What constitutes success? Healthy fish that live a long time, quite likely even breeding and having babies. Success also means having a tank that looks nice without a lot of maintenance (e.g., constantly battling excessive algae growth).

Having a successful tank is not difficult, nor necessarily a lot of work, provided you follow some common sense guidelines. These guidelines are based partly on science and partly on experience gleened from aquarists having many years experience on "the art of fishkeeping." The following list summarizes the most important rules for success. Each is discussed in more detail in subsequent sections of this document.

• Have patience. Buying a tank, setting it up and filling it with fish all in the same day is simply not possible. In fact, setting up and fully stocking your first tank will take close to two months!
• An ounce of prevention is worth a pound of cure. Providing an environment that minimizes fish stress is the key to success. As fish become stressed, their immune systems weaken and they become more susceptible to disease. Moreover, most fish medicines don't work very well, aren't worth the money, and frequently do more damage than good. Usually, the best treatment for sick fish is to relieve stress by 1) performing regular partial water changes, 2) not overfeeding, 3) checking that your filtration system works, 4) giving them enough room to live, and 5) keeping them with compatible tank mates.
• Understand and respect the nitrification cycle. Fish produce toxic wastes (ammonia) that must be broken down by bacteria through biological filtration. Most fish deaths for first-time tank owners are a direct result of not understanding the nitrification cycle and are completely avoidable. See the cycling section for details.
• Perform regular maintenance on your filter to keep it clean. Dirty (clogged) filters operate at reduced efficiency. In the case of biological filtration, a clogged filter will be unable to remove ammonia properly, resulting in fish stress and eventually death. Floss-based biological filters are cleaned by gently rinsing them in (used) tank water. Undergravel filters are cleaned through regular vacuuming. See XXX for details.
• Properly treat all tap water before adding it to your tank. Municipal water contains such added chemicals as chlorine or chloramine to make it safe for human consumption. These substances are toxic to fish and can weaken, damage or even kill fish. See XXX for details.
• Take the time to learn basic water chemistry (pH, hardness and buffering). You needn't enroll in a chemistry course, but you should know enough about water chemistry and the specifics of your local water supply so that you can keep fish happy. Every location's water source is different, and some fish won't be able to survive in your water. You can learn details about your water from a local fish store, through the use of test kits, or from local aquarium clubs.
• Keep the pH of your tank's water stable. Rapid pH changes stress fish. Tank water has a natural tendency to become acidic due to the production of nitric acid (nitrates) from the nitrification cycle. Keeping pH stable requires having adequate "buffering". If your water is soft, you may need to add buffering agents. See XXX for details.
• Avoid adding chemicals that lower the pH (e.g. "pH-Down"). Such chemicals frequently have undesirable side-effects (e.g., stimulate algae growth). Moreover, in most cases (despite what books and stores tell you) the pH of water DOES NOT need to be adjusted to make it "more perfect" for a particular species of fish. If the pH of your tap water is between 6.5 and 7.5, it is just fine for most fish. See XXX for details.
• Select fish who are native to waters having a similar chemical properties (pH and GH) to your local tap water. If you have hard water, choose hard water fish. If you have soft water, choose soft water fish. Changing the natural hardness (or pH) of your tap water can be hard work and often takes the fun out of keeping aquariums. Moreover, bungled attempts at adjustment are common and often worse for fish than the original sub-optimal water conditions. A good way to learn which fish live happily in your local water is to check with a local fish store (or club).
• Choose the fish to fit your tank. Select fish that are compatible with each other and think long-term. That 1 inch fish sure looks cute at a store. But what will you do when it gets 6 inches long and views its cohabitants as potential meals? Fish have specific minimal space requirements that are dependent on their physical size and temperment. Select fish whose needs will be met in your tank. Be sure your tank has adequate hiding places (e.g., rocks, plants, driftwood, etc.) for its inhabitants.
• Perform regular partial (25%) water changes every other week. Partial water changes serve two purposes: they dilute and remove nitrate before it accumulates to dangerous levels, and they replace trace elements and buffering that get used up by bacteria, plants, etc. Finally, regular partial water changes help insure that your tank's water chemistry doesn't deviate significantly from that of your tap water. The latter benefit is especially important should disease strike your tank; water changes are the most important step in controlling disease, and large water changes are not safe unless the chemical composition (e.g., pH and GH) of your tank's water is similar to your tap water.
• Shop only at "reputable" stores. Sadly, many pet stores are more interested in taking your money than selling you healthy fish. It is almost always worth spending a little more money to get quality fish. Diseases introduced to your tank with a new purchase fish may infect your other fish with catastrophic results. Buying a low cost fish is also not much of a bargain if it dies less than a month later.
• Properly acclimate fish (see XXX) before adding them them to your tank, NEVER add store water to your tank (it may contain diseases), and if feasible, quarantine new purchases for 2-3 weeks before adding them to your tank.

How much time and effort is involved in keeping a fish tank?

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