Why test the pH of a pond? What about dissolved oxygen? While these tests may seem very scientific for the average pond owner, they are actually quite simple and can be inexpensive. The results of pH and dissolved oxygen tests can also clarify problems that a pond owner might have in a small pond.
Why Test pH and Dissolved Oxygen Levels in the Pond?
A healthy pond is one that has a stable pH and a good level of oxygen. Fish, aquatic insects, and other pond animals need a healthy environment. Yet things can quickly get out of hand, especially in the summer and fall when heat and debris change the nature of the pond.
Are the fish in the pond gasping for air? Does the pond have a funny color or odor? Perhaps there is algae blooming all the way across the pond. Maybe the lily pads have been reproducing and now form a mat at the surface of the pond. Whatever the reason, many pond owners may suspect that there is something not quite right about their pond. Instead of worrying about pond water quality, buy a pH and dissolved oxygen kit and find the problem and the solution.
Use pH and Dissolved Oxygen Levels to Monitor Water Quality
Use a water testing kit or a water quality meter to measure the pH and dissolved oxygen levels in the pond. The pH of a healthy pond should be in the mid-range of the pH scale, right around seven to eight. The dissolved oxygen levels should be approximately three to six milligrams per liter of water.
Water quality meters are often digital and come in pond kits and pool kits. They are usually fairly inexpensive, around $30 each. Dissolved oxygen meters are more pricey and run into the hundreds, although it is possible to get a kit that combines both pH and dissolved oxygen tests.
The other option is a water testing kit. Salifert and LaMotte Company offer dissolved oxygen kits that are under $50 and have ten to fifty tests each. Many companies offer pH test kits that give the pond owner the opportunity to test water samples by placing them in a vial with a solution. These are often marketed as drinking water or pool water test kits.
What to Do if the pH and Dissolved Oxygen Levels are not Adequate
If the pH level is too high or too low, look for sources of pollution. These might be as simple as soapy water that enters the pond from a car washed on a driveway.
If there is inadequate oxygen due to an algal bloom, look for sources of pollution. Is there a lawn nearby that drains fertilizer into the pond? Perhaps there is also a lot of debris at the bottom of the pond. Get a pond filter or remove some of the debris by hand.
If there is too little oxygen due to still water, use a pond pump or fountain to move oxygenated water around the pond. Since invertebrates and fish like koi all breathe through gills, it is important to have ample oxygen in the water.
Water quality is an important aspect of pond management. When the pond is not healthy, then pond plants and fish suffer. When the pond has good water quality, it can sustain fish and will attract other wetland animals as well.
Tricia Edgar - Tricia Edgar is a gardener, environmental educator, and science writer from the Pacific Northwest.
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