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Fish Facts

There are a variety of fish and other creatures that can add a whole new dimension to your water feature. While their beauty alone may be fascinating, they also play an integral role in maintaining a balanced ecosystem.

Do I need a big pond to have fish?
The size of a pond determines how many fish it can support. No water feature can be too small, but if yours is tiny, you may only be able to have a few small fish living in it.

How many fish can I put in my pond?
The amount of surface water is what determines the amount of fish your pond can support. The common rule is that a body of water will support as many fish as can fit head-to-tail across its average diameter. If you add additional air by using a pump or air stone, you can add more fish.

What is the difference between goldfish and koi?
Goldfish and koi are species of carp, but they are from two different families. Goldfish are a mutation of crucian carp and koi are common carp (cyprinus carpio). Koi tend to move through the water at a more relaxed pace than goldfish.

What mistakes are commonly made when adding fish to ponds?
The top three mistakes are stocking the pond too quickly after filling it, putting in too many fish at once and overstocking. You can save yourself lots of money and frustration by adding a few inexpensive feeder goldfish first to make sure your water is ready.

How early can I add fish?
It is best to wait until mid-May to add fish to your water. Koi and goldfish can tolerate cold water but sudden, drastic changes in temperature can be stressful and potentially fatal.

How do I get my water ready for fish?
Ideally, water should be in your pond for several weeks before you introduce any fish.  You can use a product such as Rapitest to make sure your water is ready. Various factors can affect your fish, including pH levels and levels of Chlorine, Fluoride, Ammonia, Nitrites and Nitrates. Chlorine will evaporate in a few days but some of the other chemicals will not, so it’s important to have the water checked before adding fish, especially if you use city water.

Will I need to test my water often?
Test your water before you introduce fish and then monitor it every few weeks throughout the season. Watch your fish for signs of problems. If they seem lethargic, have a slimy appearance, rub up against objects underwater or spend much time gulping air at the surface, there is most likely a problem.

What causes the water to change?
The nitrogen cycle occurs naturally in water as uneaten food, fish waste and plant materials decay. When something disturbs the natural cycle, such as too much fish waste, harmful buildups can occur. Fertilizers washing in from surrounding lawns and gardens can also cause problems.

What and how often should I feed my fish?
Try to feed them on a regular schedule (daily or two-three times a week), giving them as much food as they will eat in five minutes. The amount they eat and what they eat varies according to how active they are, how cold the water is and whether or not they are growing.