pH Levels, Nitrites, Nitrates: What It All Means for Your Water Garden

By J. A. Young

Balanced pond water is not only necessary for the health of your pond's plant and animal life, it's attractive to look at. Cloudy, dirty water or even water that is unbalanced is unsafe for the overall health of your pond environment. While there are plenty of filtration systems and cleaning kits to employ, it will be helpful for water gardeners to understand what the elements of this balance are and how they work in the garden pond.

Any change to your pond water's chemistry will have a great impact on the plant and animal life there. While you can obtain test kits and water treatments to ensure a healthy water balance, you will first need to know what that chemistry means and how it works in your pond. When you test your pond water, you will essentially be checking levels of pH, nitrites, nitrates, ammonia and protein. Any one of these areas may require a treatment to restore it to its appropriate level.

The pH level of your pond water refers to the measurement of its acidity or alkalinity. If your pond water is under pH 6.5, it is it is acidic; if the water measures higher than pH 7.5, it is alkaline water. Not surprisingly, most pond fish require a healthy pH level that is between 6.5 and 7.5. A level that is over pH 8.5 will cause distress to your plant growth as well as harm your fish, so maintaining the appropriate level is utmost in importance for the health of your garden pond.

If ammonia is not dealt with in your pond, it will prove deadly for your fish. Even slight levels of ammonia will distress your fish because it leaves them open to infection and disease. Unhealthy levels of ammonia are caused by fish overpopulation and excess detritus, which is essentially comprised of fish waste decaying plants. A high ammonia level must be treated immediately to safeguard the life of your pond.

If your high ammonia levels remain untreated, nitrites will form in the water. Nitrites are especially toxic for fish. While the beneficial bacteria and enzymes residing in the pond water will eventually turn these nitrites into benign nitrates, it is often not in time to save the pond's fish. Consequently, nitrites must be dealt with - but dealing with the ammonia is first and foremost to guard against a nitrite problem. A good filtration system will help in this area.

Nitrates are a form of nitrogen; they are not harmful to fish and are basically food for your pond's plants. In other words, they are good things. But, an excess of nitrates cannot always be safely absorbed by the pond’s plant life. In such cases, an over-abundance of nitrates can lead to methane gas production, blanket weed, algae, high acid content in the water, etc.

Protein in the pond water means a buildup of animal protein that usually stems from decomposing matter in the form of fish food, fish waste and other animal organisms in the pond. This too must be treated to avoid excess levels of ammonia, nitrites and nitrates and an unbalanced pH level. Of course, there are always potentially harmful bacteria that may find their way into the water - like heterotrophic bacteria which generally form in unfiltered water. Getting rid of unwanted species like this is also necessary for the life of the pond.

Hopefully, this will help all the potential water gardeners out there and not detract them from incorporating a pond into the garden. Garden ponds do require routine maintenance, but a decent filtration system, routine water testing and occasional water treatments will usually make for a beautiful and healthy pond. The joy far outweighs the work!