Whether you have too much or too little, many different problems can stem from inappropriate levels of oxygen in your pond or lake. If you want a healthy pond you will have to learn to manage it. There are a few ways to go about this.
When looking at oxygen in water, it is referred to as dissolved oxygen (DO). It is usually measured in parts per million (ppm). There are three main methods of determining dissolved oxygen concentrations in water:
- An electrochemical or optical sensor, which is the most accurate
- Colorimetric sampling, which will give you a basic approximation
- Winkler titration, which is accurate, but more difficult than other methods
If your dissolved oxygen levels are decreased below 6 ppm, you will probably notice some sort of algal bloom happening in your pond. Usually an increase in your levels of nitrogen and phosphate is what causes this chain of events. To raise the DO again, you will need to increase the lake aeration and flow rate in the water. One sure-fire way to do this is to introduce an aerator. Depending on the size of your pond, you may want more than one. Take is slow and test as you go.
It is less common to have a problem with too much oxygen. This over-aeration can occur if the water is exposed to rapid temperature changes or if you have a high pressured dam or waterfall within your body of water. This will basically effect what type of animal life will be able to live in the water. For example, trout require cold water and high levels of DO. On the other end of the spectrum, pike like warm water and do not require much oxygen to survive.
Almost everything in your pond either uses or produces dissolved oxygen in some way- that’s what makes it such a key characteristic of concern in ponds and lakes. If you have a handle on your oxygen, you’re well on your way to being a pond boss!