Owning and managing a pond or lake oftentimes seems a much more complicated endeavor than expected. There are a lot of moving parts that determine the health of a body of water. Once you get a grip on a few key components, it all gets easier from there.
The amount of dissolved oxygen to be found is very important for the respiration processes of every living thing in your pond as well as the natural processes of decaying matter. You should expect a level of 6 parts per million (ppm). If there is not enough oxygen in the water you may see symptoms such as an algal bloom. This is usually the fault of inadequate water flow rates or an increase in nitrogen. Usually, pond aerators and fountains can help to introduce more oxygen.
pH is measured on a scale of 0 to 14, from basic to acidic- from soap to lemons. pH is defined as the measure of the potential for hydrogen. A neutral reading, or that of around 7, is ideal for a lake. However, anything ranging from 6.5 to 9 is acceptable, because the reading will naturally fluctuate with time of day and season. It is easy to test this on your own with at-home kits.
Hardness is the measure of alkaline earth elements such as calcium or magnesium, which are helpful to fish and other vertebrates living in your pond. Alkalinity, otherwise known as temporary hardness, is the ability to resist change in pH levels. A more mature pond will have a higher alkalinity rating, which is a good thing.
Although it seems like a lot now, as you spend more time with your pond you will come to recognize these variables working together as second nature. You might be able to tell if you need to check your pH based on a smell, or your dissolved oxygen based on the color. Get to know your pond!