Do Septic Additives Work?

If you have a septic system, proper septic maintenance can mean the difference between a long-lasting, trouble-free system and one that ultimately costs thousands of dollars in repairs or replacement. Many people receive conflicting advice about what maintenance is necessary.

In Florida, most onsite professionals recommend that septic tanks be pumped every 3 to 5 years. Pumping the septic tank removes solids. Some septic companies have another solution — use low-cost septic additives on a regular basis to reduce the need for the more costly pumping. Additionally, when a septic system is in trouble and a costly repair or replacement looms, some additives claim a quick fix.

So what’s the truth? Some experts say additives do more harm than good. Some believe that they are not harmful, but they don’t do much of anything at all, except cost money. Other than the septic additive manufacturers themselves, it does not appear that any scientist, engineer, academic, or government source recommends the use of septic system additives.

Septic System 101

In houses with septic systems, when the toilet flushes or the washing machine runs, wastewater leaves the home and collects in the septic tank. There, the natural bacteria in waste break down most of the solid material into a liquid or gas. Heavy solids or bits of plastic or other material that can’t break down settle to the bottom of the tank and form the sludge layer. Lighter substances such as grease or oil float to the top, this is called the scum layer. In between these two layers is the relatively clear liquid. This is called effluent when it flows out the septic tank. It is distributed into the drainfield or absorption area where it percolates down through the soil.

Septic Additives

Septic tank additives, also called septic tank treatments, cleaners, restorers, rejuvenators, and enhancers, fall into two categories: chemical and biological. Chemical additives are marketed to open up clogged drains and to break up grease and oil. They include active ingredients such as sulfuric acid which can be highly corrosive and cause structural damage to a septic tank. Additionally, it is generally recognized that exposing soil and groundwater to harsh chemicals can harm the environment.

Biological additives are made from bacteria, yeast and/or enzymes. They are said to work as starter agents in new systems and to increase the efficiency of breaking down the solids in existing systems. Biological additives are often sold as routine maintenance, flushed down the toilet on a monthly or weekly basis to assure the septic system’s “balance.”

Of particular concern is the claim that some products reduce or eliminate the need to pump the septic tank on a regular basis. Pumping solids out of the tank is a vital and basic practice to septic system maintenance. As long as wastewater is entering a septic tank, solids will be present. The job of the septic tank is to keep as many of the solids in the tank (retention and settling) – not let them pass on to the next treatment process of the drainfield. If a product claims reduction or elimination of the need to pump, the obvious question is “where do the solids go if they are no longer in the tank? The only place they can be, in the drainfield!


Most chemical additives ultimately harm the septic system and some, the environment. Biological additives are mostly benign, but unnecessary. What the septic system needs to work properly is introduced the first time you flush the toilet!

Call us for septic tank pumping, cleaning or septic tank repair or replacement or if you need a drainfield repair or replacement in Deltona, Debary, Deland, Orange City, Osteen, Enterprise, Pierson, Sanford, Lake Mary, Oviedo, Orlando or other cities in Central Florida.