Drain Cleaners for Septic Systems

Written by Rebecca (Becky) Blanton
on Feb 27, 2010

To ensure our content is always up-to-date with current information, best practices, and professional advice, articles are routinely reviewed by industry experts with years of hands-on experience.

Reviewed by
H.R. Helm
on Nov 17, 2021

You can use drain cleaners in a septic system as long as you use the correct kind. Septic systems rely on live bacteria in the septic tank to break down household waste. Drain cleaners, such as those used in non-septic systems, can kill the bacteria in a septic tank, damaging your system. Instead, clean your septic-tank systems with the correct products to keep it from smelling and having other issues in the future.

Why You Shouldn’t Use Non-Septic Cleaners

Studies show it only takes approximately 12 grams of bleach, or any other non-septic drain cleaner, to kill all or most of the bacteria in a septic tank. Never use bleach or non-septic drain cleaner, unless you're prepared to have your system pumped out and to pay the extra cost of cleaning out your entire system.

Acceptable Drain Cleaners For Septic Systems

There are a variety of products specifically designed for use in a septic system. Look for cleaners with a crystallized sodium-hydroxide or natural-enzyme base such as the following below.

Drano Crystals

This product works wonderfully to clean a septic system. However, you should follow the directions on the product carefully, as it is caustic and can cause burns. Always use with eye and hand protection.

Biokleen Bac-Out

This product uses enzymes and natural ingredients to dissolve grease and clogs. Although more natural than the previous cleaner, you should still follow the directions carefully and avoid skin contact.

BioGuard Plus, Drain and Septic Cleaner

This product is biodegradable. It is also non-toxic, non-caustic, and non-pathogenic. You can easily find it in stores or online.

Homemade Drain Cleaner

For a homemade cleaner, pour 1/2 cup salt and 1/2 cup baking soda down your clogged drain. Then, pour 6 cups of boiling water after it. Allow to sit overnight and then flush with hot water.

Using the appropriate drain cleaner for your septic system, along with completing regular inspections, will ensure your tank runs properly. Remember to never use bleach or other non-septic cleaners and stick to ones made specifically for septic systems.