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How Big Should a Septic Tank Be?

Installing Septic Tank
Septic tanks are commonly found in rural homes, where they take the place of municipal sewers. If you own a house with a septic tank, you've probably already figured out that its size matters. Septic tanks that are too small create many problems for homeowners. Before you can understand why a septic tank's size matters, you must first know how a septic tank functions. 
A septic tank is an underground tank that collects wastewater. When the water in the tank reaches a certain height, it drains into a pipe that leads to a part of the yard called the drainfield. Solid pieces that enter the septic tank settle to the bottom. Periodically, these solid pieces must be pumped out of the tank, or the tank will clog.
How Many Gallons Should Your Septic Tank Hold?
The minimum-size septic tank for a home with one to three bedrooms is 1,000 gallons. Each additional bedroom increases the minimum size of the septic tank by a few hundred gallons.
This is because the number of bedrooms in a home is usually proportional to the amount of wastewater that home may produce. A home with many bedrooms may have many people living inside. Each person will flush the toilet, take showers, wash dishes, and do other things that will fill the septic tank with waste water. The more people, the bigger the septic tank must be.
What Happens If Your Septic Tank Is Too Small?
If your septic tank is too small, it will fill up quickly. Solids will sink to the bottom of the tank but may not be able to settle properly because the tank is small and fills fast. This problem can cause small pieces of solid matter to clog the pipe leading to the drainfield and may ultimately result in a clog. Undersized septic tanks must be pumped frequently or they will break.  
Can a Septic Tank Be Too Large?
Oversized septic tanks are not as big a problem as undersized septic tanks; however, they may not function very efficiently. Septic tanks that are too large may not create bacteria efficiently.
Your septic tank relies on bacteria to break down solid waste. Bacteria cause the solid waste to turn into a liquid so it can empty into the drainfield with the rest of the home's wastewater. If the formation of bacteria is interrupted because the tank is too large, the tank may need to be pumped more frequently than otherwise necessary. 
How Often Should You Pump Your Septic Tank?
If your septic tank is properly sized for your home, have it inspected every three years. Your septic tank professional may not choose to pump it at that time, but they should still look at it to ensure that a pumping isn't necessary. If your septic tank is too small, you may need to have it inspected and pumped annually. 
What Should You Do If Your Septic Tank Is Too Small?
If your septic tank is too small, talk to a septic tank professional to have it replaced with a larger tank. Your septic tank professional can determine how big your septic tank should be based on the number of bedrooms or people in your household, and then your professional can make a recommendation for replacement. Get quotes from multiple septic tank professionals before proceeding. 
For more information about how you can maintain your septic tank, contact an expert in the industry. At The Nibbler Company, we're happy to give you information about septic tank size and other important pieces of information. Give us a call today to find out more.