Your Septic Tank: What You Need To Know

Depending on the number of bedrooms, a septic tank (holding tank) can range in size from 500 to 3,000+ gallons (1,000 gallons being average). It is an important part of how septic systems work.

Your tank is set up to only allow liquid to pass through to the drain/leach field. This is in order to not clog the small weep holes and dry soil with suspended solids. Microbial digestion and separation perform this task.

Within your tank, denser solids sink to the bottom and form “sludge.” Lighter solids, such as oil and grease, move to the top and form the “scum layer.”

Between these upper and lower layers should be all liquid. Inside your septic tank there are a series of baffles. These baffles work to keep the scum layer held at the top and the solids pooled at the bottom. That way, only liquid can flow to the outlet pipe. Experts call this the “process of separation.”

The only other thing you really need to note is that your septic tank turns solids into liquid through the process of “Microbial Digestion.” Sludge and scum is liquefied by natural enzymes and bacteria within your tank. Municipal waste water treatment plants all throughout the country use this same process.

After microbial digestion occurs, all the liquefied sewage flows out of the tank and into the leaching area (the drain/leach field).

To learn more about microbial digestion, check out another of our great products, Bio-Septic Boost.