2torial #0693:
Learn2 Build a Garden Pond (continued)

Add the fish

When you add your fish, remember that you're creating their entire world. If one element is off, the whole system can be affected. Follow these safety tips for a smooth introduction:

Prepare the water. As mentioned earlier, most tap water is treated with chemicals. Some of these chemicals (particularly chlorine and chloramine) are toxic to fish, so it's critical to prepare the water for their arrival. To do this, you'll need the following, all available at aquarium supply stores:

• Water conditioner, which removes the harmful chemicals

• A biological aquarium supplement, which is a colony of "friendly" nitrifying bacteria that convert ammonia, or fish waste, into chemicals that the pond's plants can use

• A pH level testing kit, to make sure the acidity and alkalinity levels are safe for the fish

• Some pH "buffers" (if necessary), which can raise or lower the pond's pH levels

Add the conditioner to the water first, using the instructed amount per gallon (or liter) of water. Then add half of the instructed amount of the biological supplement. Next, wait at least a month. This time allows the conditioners, the bacteria, and the plants to work together and stabilize the environment. Once a month or so has passed, test the water's pH levels, following the kit's instructions. When everything checks out, add the rest of the biological supplement, then it's time to move in the new tenants.

Add the fish. You can buy goldfish at most aquarium and pet stores. Pick up their food while you're there. The store will put your fish in a plastic bag for transport. (If the trip from the store to your home will take more than half an hour, leave some oxygen in the bag for safety.) When you get to your home, submerge the bag in the pond, open it, and let the fish swim out into their new home.

Note: It's critical that you not overstock your pond. Too many fish create a waste level that will overwhelm the pond's ecological balance and result in dead fish. A rough gauge is 1 inch (2.5 centimeters) of fish for every 10 gallons (45 liters) of water. Use the fish's adult length in the equation (ask the seller). To be extra safe, buy about half of this number. You can add more later.