List of Things Not to Put in Septic Tank: From Chemicals to Bacon Grease

One of the keys to a well-working septic system is to avoid putting things in a septic tank that don’t belong there. Whether it’s chemicals that can harm the pH balance of the tank or non-flushable items like cat litter, it’s essential to know what not to put down your drains or in your toilet. Here’s a comprehensive list of things not to put in a septic tank. 

Why It’s Important Not to Put Certain Things in a Septic Tank

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A clogged or overflowing septic tank can be costly and messy to fix. Here are the main benefits of putting only the right things in your septic tank:

• Prevents clogs and backups

• Prevents overflowing or seeping leach fields and septic tanks

• Keeps the natural bacteria in your tank healthy and able to break down sludge

• Prevents toxic sewage leaking into your home

• Prevents sewage smells outside

• Avoids the health hazard of an overflowing tank

• Saves money by reducing repair and pumping costs

Here’s a comprehensive list of things not to put in your septic tank.

Chemicals

Chemicals can harm your septic system by killing off the natural bacteria that break down the sludge in your tank. When the bacteria is stifled or killed, your tank gets fuller faster, leading to more clogs, backups, and the need to pump your tank more often than usual. Chemicals can also throw off the pH balance in your tank and corrode the pipes in your septic system. 

You should avoid putting weed killer, insect killer, and paint in your septic system, as it can poison the wastewater that reenters local rivers, lakes, and coastal waters. If you use household cleaners like bleach, disinfectants, and drain and toilet bowl cleaners, use them only in moderation. Be sure to follow the manufacturer’s instructions. Consider switching to natural cleaning products to ensure the healthiest septic tank possible.

Here are the list of chemicals to avoid putting in your septic tank: 

• Chemical-based cleaning products

• Bleach

• Gasoline

• Paint thinners

• Solvents

• Photographic chemicals

• Weed killer

• Insect killer 

• Caustic drain openers and cleaners

• Fabric softeners

Fats, Oils, and Grease

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Putting fats, oils, and grease down your drain can cause them to get stuck to the sides of your pipes, trapping more debris and leading to clogs. In addition, the bacteria in your tank can’t break down these substances very well, causing them to float in the septic tank and fill it up faster than usual. 

Here are the fats, oils, and greases not to put down your drain: 

• Cooking oil of any kind

• Butter

• Bacon grease

• Animal fats

• Drippings from meat

• Gravy and fat-based sauces

• Mayonnaise

• Poultry skins

• Salad dressing

• Peanut butter and other nut butter

• Grease

Medications and Cosmetics

While it can be tempting to flush leftover medications down your toilet or drain, it can ruin the bacteria balance in your septic tank. It also pollutes the wastewater and contaminates people and animals that reuse the water. You should dispose of all medications and pharmaceuticals through a local pharmacy or hazardous waste facility. Cosmetics can also contaminate water, and lotions can cause clogs. Consider switching to natural products when possible, including hand soap that isn’t antibacterial. 

• Antibiotics

• Medicines and pharmaceuticals 

• Antibacterial soap

• Cosmetics 

• Hand creams 

• Lotions

• Moisturizers

Sanitary and Personal Items

Putting non-biodegradable items down your drain can lead to clogs and your septic tank filling up faster than usual. The bacteria in your septic tank can’t break these items down, leaving them to sit in your tank until it is pumped. Some of these items can also cause clogs in the pipes and sewer lines.

• Feminine hygiene products

• Wipes (even those labeled as flushable)

• Cat litter

• Floss

• Cotton swabs

• Contact lenses

• Bandages

• Cigarette butts

• Paper towels

• Condoms 

• Disposable diapers

• Ear plugs

• Dryer lint

• Plastic, latex, or metallic objects

• Pieces of trash

Items That Decompose Slowly

Some items might seem like they could go down the drain, but they can clog the system and cause the tank to fill up faster. Many of these materials can’t be broken down by bacteria, leaving them to take up your tank space. Instead of putting these down your drain, throw food scraps, coffee grounds, and eggshells in a compost bin to reuse in your garden.

• Hair

• Dirt

• Coffee grounds

• Large food scraps

• Fruit pits

• Eggshells

• Potato peels

• Onion peels

• Hard foods

• Dry, expandable foods like pasta and rice

Septic Tank Additives

Several types of septic tank additives claim that they enhance your septic system’s functionality. But in fact, these additives aren’t proven to work. In many cases, they can lower the performance of the natural bacteria in your septic tank, leading to more sludge and a fuller tank. It’s best to stay away from septic tank additives. Instead, you can naturally increase the bacteria in your septic tank by adding three rotten tomatoes down the garbage disposal every three months. 

Maintain Your Septic System and Know When to Call for Help

Beyond avoiding the list of things not to put in a septic tank, you should also check to see if your septic tank is full every three to five years. Most tanks need to be pumped that often, but sometimes more frequently. If you notice the warning signs of a clogged sewer line, contact a local septic tank repair company to inspect your septic system as soon as possible. A clogged sewer line can lead to leakage, smells inside and outside your home, and health concerns for your family and the surrounding area.

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