There are many different types of products available to treat your septic tank. Organic solvents help get rid of grease in your pipes and septic tank. Biological treatments are made up of yeasts, bacteria and enzymes. The manufacturers of all of these products claim that they will in one way or another help your septic tank. The most frequent claim is that they will reduce the necessity of pumping and extend the life of the tank.

On the Other: Experts Feel Treatments Do Not Work

Most experts believe that biological treatments won't hurt your system but that they also won't help. The general consensus is that there are millions of bacteria in the system, and adding more just doesn't help. Organic solvents can actually cause ground-water contamination. The inorganic treatments will often kill the bacteria, effectively shutting down the biological decomposition of material in the system.

Bottom Line

Expert opinion, including that of several universities and experts in the field, is that septic tank treatment is not very useful. These experts also believe that the life of a septic tank is in the range of 20 years, and nothing you can do will extend the life of the tank, so instead of spending money on those treatments, set it aside to replace your 20-year-old system.

Source:

University of Missouri Extension: Septic Tank Additives

Septic Tank Info: Care and Feeding of Your Septic Tank

More Information:

CSU Chico: Design and Performance of Septic Tanks