Fish are one of life’s simpler joys. They exist in the wild with few problems and little intervention by man. Nature provides for the well being of fish via a sprawling and complex ecologically balanced micro-system. So perfectly balanced is that system that few predators outside of human beings are a substantial threat to them.

We’ve all seen how man has disrupted this delicate balance with devastating results. Fish die-offs in the Atlantic Ocean, kill-offs in the Straits of Alaska, genetic mutations in the Great Lakes. Wherever humankind has meddled, fish—and other animals as well, of course—have paid the ultimate price.

Now we ask not only to meddle in nature, but also to recreate it. We dare to turn our eyes toward the skies and say, “Oh, Lord of the Universe, Who hath created such wondrous and matchless things, give us a shot at it!”

And that’s exactly the role we take on when we build a fishpond.

But what is a fishpond, exactly? If you say, “It’s a place imitative of nature, where all things must function in harmony and balance, toward which goal the pond keeper must be prepared to work as long and as hard as it takes,” I would not only advise you to stock your pond with fish, but also recommend what colors.

Setting up a fishpond means diligently working to maintain its health and balance. Only by doing so can you hope to have a healthy, happy colony of fish to entertain and amuse you for as long as you desire.

Happy? Yes, fish can feel happy, and they can definitely be amusing. They can reach out in an effort to relate to you. In doing so, they can offer a harmonious link to the nature of a world that is foreign and even deadly to us—the world of underwater life.

Perhaps that is the greatest allure that fish hold for us—their ability to live in what to us is a hostile environment. We look at them and marvel. They have no lungs, and yet they breathe. They have no arms and legs, and yet they move. The have no ears, and yet they “hear.”

What fish don’t have is the ability to control their own environment. That’s where we come in.

Requirements
Most fish require several things in order to survive. They need a high oxygen level in the water. They need sunlight and shade. They need ambient temperature between 40 and 90 degrees F, depending upon the species. They need food, vitamins, minerals, and all of the other supplements that most living things need for survival and which they obtain through various complex mechanisms.

Most fish won’t survive, or at least remain healthy, with certain other elements in their environment, including high ammonia levels, high or low pH levels, and high nitrite, nitrate, chlorine, and chloramine levels, not to mention a whole host of other toxic chemicals.

Thankfully, there are some early warning signs for the observant aquaculturist that things are not as they should be. The first sign is a fish floating belly up. A dead fish is absolutely the first and surest sign that you need to take some drastic steps and take them fast! Unless the fish died of disease or old age, which for a goldfish means from two to three decades, there is something wrong with the makeup of your water. You need to do an immediate 50% water change (make sure that the temperature of the new water is close to that of the old) and begin testing for signs of high ammonia or nitrate levels, followed by chlorine, chloramines, and a high or low pH.

Most likely, if the fish died suddenly and without any warning, the culprit is ammonia. A quick water change is a first step toward correcting the problem.
Swimming near the surface of the water, gasping for air, is another sure sign that fish are unhealthy. They are attempting to ingest enough oxygen through their mouths to make up for what they cannot process through their gills. That could mean that your pond’s water is low on dissolved oxygen. It could also be a sign that nitrate or ammonia poisoning has damaged the fish’s gills to the point where they are no longer able to function properly. In either case, a quick water change is required.

A third sign that fish are unhealthy is their failure to answer the dinner bell. Fish are ravenous feeders. Get in the habit of talking to them whenever you feed them—preferably in the same spot each time so that they get used to coming to you. This offers an excellent opportunity to observe the fish up close to make sure that they all appear healthy. If, come feeding time, all but one or two show up for lunch, there’s a good possibility that the missing fish are ill. Again, a 50 percent water change and further testing are indicated.

There are other diseases and problems that can affect your pond fish, and we’ll go into them later. But, for now, keep in mind that, if you monitor your pond regularly and test for harmful imbalances at least every other day depending upon the size of your pond (small ponds and containers require a closer watch), you should rarely have to worry about such things.