The most important reason I would suggest an aeration system is for the health of the fish. Oxygen levels of around 5mg/L are ideal for healthy fish production. Once it starts going below 5mg/L fish growth will slow and disease can become more prevalent. Once the dissolved oxygen concentration starts getting around 2mg/L or less, fish kills will likely result. Fish kills can happen during the summer or winter months, so once a system is installed I recommend them running full time. Also there are studies that show if oxygen levels are above 5mg/L that fish growth can increase in fact some show that a concentration of around 8g/L can show the best growth rates in fish.
Aeration can also help with water quality features. It will help speed up the decomposition process under the water resulting in cleaner healthier water with less chance of toxins building up. These toxins and gases produced from decomposition are released into the atmosphere due to the pond being constantly turned over. With the decomposition process being sped up, there are less excess nutrients available in the water column resulting in less growth of unappealing algal blooms. This will also help reduce the amount of that black muck buildup, that when you walk through it smells like rotten eggs. Over time and in combination with the appropriate microbes you can nearly eliminate that muck or at the least greatly reduce it.
Another advantage that is often overlooked is habitat. The column of bubbles going up through the water column can actually provide additional habitat, especially for younger fish making up the prey base. This can result in more prey availability and potentially increase the carrying capacity of a water body. Also by keeping the pond turned over and having the thermocline eliminated, this allows fish to use the entire water column year round rather than being confined to the area above the thermocline that has sufficient oxygen.
Finally, there is one other reason to install an aerator that many people do not think of and only would benefit those in the Northern climate. Having the diffuser set near the shore, so there is open water in the winter months along the shore line. Why would you want to do this you might ask? Well for deer hunting. Having open water on your property can be better than the best food plot you can imagine once all of your neighbors ponds are frozen over. Even if you don’t hunt these can be great to view wildlife on your property and allow them to have the necessary resources all year long.
Remember to manage today for a better tomorrow!