Here’s a comprehensive household list of items that can potentially harm the beneficial bacteria in a septic tank. This includes products that kill bacteria, disrupt the microbial balance, clog the system, or introduce non-biodegradable materials.
🚫 1. Cleaning & Disinfecting Products (Antibacterial / Antimicrobial)
These are the most harmful because they directly kill septic bacteria.
Bleach & Chlorine Products
- Chlorine bleach (e.g., Clorox bleach)
- Color-safe bleach
- Chlorine-based toilet bowl cleaners
- Pool shock or chlorine granules
Antibacterial & Disinfecting Cleaners
- Antibacterial sprays
- Disinfecting wipes (e.g., Lysol Disinfecting Wipes)
- Disinfectant sprays (e.g., Lysol Disinfectant Spray)
- Hospital-grade disinfectants
- Quaternary ammonium (“quats”) cleaners
- Phenol-based cleaners
Antibacterial Soaps
- Liquid antibacterial hand soaps
- Antimicrobial body washes
- Products containing triclosan or triclocarban
🧴 2. Personal Care Products (When Used Excessively)
These don’t always kill bacteria outright, but large amounts disrupt balance.
- Shampoo
- Conditioner
- Body wash
- Face wash
- Liquid soap
- Toothpaste
- Mouthwash (especially alcohol-based)
- Hair dye
- Hair bleach
- Nail polish remover (acetone)
- Makeup removers
- Acne treatments (benzoyl peroxide, salicylic acid)
- Medicated creams
- Sunscreen
- Lotions and creams (in excess)
🧼 3. Laundry Products
- Powdered laundry detergent
- Liquid laundry detergent
- Laundry pods
- Fabric softener
- Dryer sheets (chemicals enter through washing residue)
- Oxygen bleach
- Stain removers
- Whitening agents
- Heavy-duty degreasers
🧽 4. Kitchen & Dishwashing Products
- Dish soap (especially antibacterial)
- Automatic dishwasher detergent
- Dishwasher pods
- Garbage disposal cleaners
- Drain cleaners
- Oven cleaner
- Degreasers
- Silver polish
- Metal polish
🧪 5. Chemical Drain & Plumbing Products (Extremely Harmful)
- Caustic drain openers (lye-based)
- Acid drain cleaners (sulfuric acid)
- Foaming drain cleaners
- Root killer chemicals (copper sulfate)
- Chemical septic additives (some are harmful)
🛢 6. Automotive & Workshop Fluids
Never pour these down drains:
- Motor oil
- Transmission fluid
- Brake fluid
- Antifreeze
- Gasoline
- Diesel fuel
- Kerosene
- Paint thinner
- Turpentine
- Solvents
🎨 7. Paint & Home Improvement Materials
- Latex paint (in large amounts)
- Oil-based paint
- Paint thinner
- Varnish
- Wood stain
- Polyurethane
- Adhesives
- Epoxy
- Caulk
- Grout wash residue
💊 8. Medications & Pharmaceuticals
These severely disrupt septic bacteria.
- Antibiotics
- Antifungals
- Antivirals
- Chemotherapy drugs
- Hormonal medications
- Expired medications
- Veterinary medications
🧻 9. Paper & Hygiene Products (Non-Biodegradable or Slow to Break Down)
Even if labeled “flushable,” many cause problems.
- Flushable wipes (e.g., Cottonelle Flushable Wipes)
- Baby wipes
- Disinfecting wipes
- Paper towels
- Facial tissues
- Feminine hygiene products
- Tampons
- Pads
- Cotton balls
- Cotton swabs
- Dental floss
- Condoms
- Diapers
- Cat litter (any kind)
🧂 10. Food & Kitchen Waste (Harmful in Excess)
- Cooking grease
- Bacon fat
- Lard
- Butter
- Cooking oils
- Coffee grounds
- Eggshells
- Bones
- Rice (swells)
- Pasta (swells)
- Starchy foods
- Large quantities of food scraps
🧪 11. Pest Control & Yard Chemicals
- Insecticides
- Herbicides
- Fungicides
- Weed killers (e.g., Roundup)
- Fertilizers (when entering drains)
- Termite treatment chemicals
💨 12. Miscellaneous Household Chemicals
- Air freshener liquids
- Carpet shampoo chemicals
- Steam cleaner detergents
- Rug cleaners
- Upholstery cleaners
- Fireplace ash (large quantities)
- De-icing salts
- Photographic chemicals
⚠️ 13. Things That Kill Bacteria by Volume (Even If Not Toxic)
Even septic-safe products can harm bacteria if overused:
- Excessive pump-outs (every year)
- Excessive water (flooding tank)
- Large loads of laundry back-to-back
- Hot tub draining into system
- Excessive garbage disposal use
🚨 14. Items That Should NEVER Be Flushed (Even If “Septic Safe”)
- “Flushable” wipes
- Dental floss
- Hair
- Bandages
- Cigarettes
- Cat litter
- Paper towels
- Disposable mop pads
