Eco-friendly drain cleaner: enzyme versus chemical, honestly compared

Enzyme (bacterial) versus chemical cleaners

• Enzyme or bacterial cleaners: use enzymes or live bacteria that feed on organic buildup, such as food residue and grease, in the pipe. They work slowly, often over hours or overnight, and are usually used regularly as upkeep.
• Chemical cleaners: use strong ingredients such as lye (a caustic), acids or bleach-based formulas to act quickly on a clog. They can be hazardous to skin, eyes and lungs, and to some pipes and fixtures. Follow the label closely.
• Mechanical tools: a hand drain snake, a hair catcher and a plunger can clear or reduce many clogs, with no chemicals.

An honest word on what enzymes can do

Enzyme cleaners are a gentler option, but they are slow, and they are generally not designed to clear a fully blocked drain or a physical obstruction, such as a clump of hair or an object stuck in the pipe. Many are meant for drains that are starting to run slowly, or for regular upkeep. If water is not draining at all, an enzyme product is probably not the right tool, and we do not claim that any product will clear a particular clog. Results depend on the pipe, the cause and the product.

Septic systems

Some products say they are septic safe. That is a maker's claim, and septic systems differ. Strong chemical products are often advised against for septic systems, because septic tanks rely on bacteria, and enzyme or bacterial products are often described as compatible. Check the label and ask your septic service or plumber about your system.

Safety rules that matter

• Never mix drain cleaners with each other or with other cleaning products. Chlorine bleach products and acidic products can release dangerous gas when combined. Use one product at a time, and follow the label's directions.
• Do not use a plunger on a drain that has a chemical cleaner in it. The liquid can splash back and burn skin and eyes. Read the label, and wear eye protection and gloves if the label says to.
• Ventilate the room, and keep children and pets away.
• Keep products in their original containers, out of reach.
• If a clog will not clear, or if you are not sure what was put in the drain before, call a plumber. Do not keep adding products.

Our angle: cost per treatment, and what you are really buying

Most enzyme products are used on a schedule, such as a dose per week or per month, so the useful number is the cost per treatment, not the price per ounce. Look at the dose in the directions, work out how many treatments a bottle gives you, and divide the price by it. Then multiply by the treatments you expect in a year. A chemical cleaner may cost less per bottle but is used rarely, while an enzyme cleaner costs more over time and does a different job. Also add the cost of a hair catcher or a drain snake, which can be the best value of all.

1. Find the dose per treatment in the directions.
2. Divide the bottle size by the dose to see the treatments per bottle.
3. Divide the price by that number and compare with other products and with a hair catcher.