Dissolved Oxygen Levels

diffused aeration system increasing the dissolved oxygen levels in a reservoir

In any lake, pond or reservoir, no matter the size, it’s important to have sufficient dissolved oxygen (DO) Levels. Dissolved oxygen is typically measured in parts per million (PPM). The minimum dissolved oxygen level you should be aiming for is between 4 and 5 PPM.

How can I prevent my fish dying? 

If the amount of dissolved oxygen in your lake or reservoir is lower than 4-5PPM, your fish within the water body could die from suffocation. Stratification, an oxygen deficient layer of water at the bottom of your pond or lake, is another possible side effect of low oxygen levels. This can cause plant life within your pond or lake to die off. If the dead plant life is not removed it will rot. This causes silt and a build-up of nitrate and nitrate levels This eventually leads to a build-up in ammonia. There is also a risk of releasing dangerous toxins into the atmosphere from potential anaerobic waste digestion.

What exactly causes low dissolved oxygen levels?

Dissolved Oxygen LevelsLarge amounts of algae and aquatic plants are the main culprits, as they absorb a great deal of oxygen after nightfall. High silt levels will also decrease dissolved oxygen levels in a lake or pond, releasing harmful gasses into the water. Finally having too many fish in your pond or lake can reduce your oxygen levels. This is due to not only the oxygen consumption but also the increase in waste materials produced.

In a natural, ecologically balanced lake there would be little requirement for aeration. The added pressures exerted upon many lakes and reservoirs, during spring and summer especially, means added aeration is an essential management tool for most resevoirs, lakes and ponds.

A water body with a healthy ecological balance is heavily dependent on oxygen. This includes fish stocks, microscopic bacteria essential for the processing of organic waste, the oxidisation of silt, the processing of harmful gasses or nutrients and a number of other processes.

We can help you increase your dissolved oxygen levels with our diffused aerator range

Read our advice articles on our website or on LinkedIn