Why Aerobic Septic Systems Are Better Than Anaerobic

Most septic systems process organic waste by allowing solids to settle at the bottom of the septic tank and by creating an environment for anaerobic bacteria to break down organic matter. While offering some level of operational efficiency, the performance of this type of septic system pales in comparison to septic systems that have been converted to an aerobic bacterial environment.

By comparing key aspects of septic system’s performance, it is clear how superior the aerobic environment performs. By measuring the efficiency at breaking down organic waste, aerobic bacteria blows away anaerobic bacteria. Because aerobic bacteria uses oxygen in its respiration process, it is able to breakdown up to 90 percent of the organic material in the septic tank, leaving 10 percent to exit to the drainfield.  An anaerobic septic system can export up to half of the organic material that enters the tank.

Oxygen is key because it is the electron acceptor that kicks off the many complicated chemical reactions taking place within the aerobic bacteria. Oxygen is a far more reliable electron acceptor for aerobic bacteria than any of the electron acceptors for the anaerobic bacteria. As a result, the anaerobic bacteria respiration processes are just not as efficient or as fast paced as the aerobic bacteria. Bacteria for bacteria, the anaerobic bacteria just can’t process the same amount of waste as its aerobic counterpart. In the anaerobic system, a drainfield killing biomat thrives because so much organic material is exported to the drainfield from the septic tank.

Another key aspect of septic system performance is smell or odor. One of the anaerobic bacteria’s candidates for electron acceptor is a molecule that contains sulfur, the element that gives off a rotten egg odor. When this molecule is used, sulfur is released, causing an obnoxious and sickening odor to emanate from the septic tank. Aerobic bacteria, on the other hand, bypasses this molecule – it does not need it because it uses only oxygen as its electron acceptor. The consequence of this is that aerobic septic tanks do not have a rotten egg odor because sulfur is never liberated from the molecules it is contained in.

Anaerobic bacteria can also promote the creation of sulfuric acid when conditions are right. This corrosive acid will dramatically reduce the service life of concrete and steel tanks, causing expensive replacement years before it should. Many times, homeowners are unaware this damage is occurring. It is silently progressing underground and, unless the homeowner regularly inspects the concrete septic tank riser and tank, will become an expensive surprise as tank replacement is usually the only option. Again, this condition is a result of the candidates the anaerobic bacteria have for oxidizing agents. Since aerobic bacteria only use oxygen for respiration, this condition does not occur. If your septic tank riser is showing signs of deterioration it can be replaced with a plastic septic tank riser.

Aerobic bacteria allows a septic system to have a long and useful service life, something most homeowners absolutely desire. It is safe and relatively easy to convert any anaerobic system to an aerobic system and can be performed at any time. The key is to perform the conversion in a controlled manner, keeping the settling processes intact in the septic tank while the conversion and subsequent aerobic bacteria bloom occurs. There is no downside to this conversion and homeowners can push out a stressful and expensive septic system replacement indefinitely.

Share this post:

From the same category: