Can I use Stain Remover with septic and greywater systems?Updated 13 days ago
TL;DR: Yes. Stain Remover is suitable for septic tanks and greywater systems at the recommended dose. The enzyme-based formula is phosphate-free, low in sodium, and readily biodegradable. Stick to normal doses and follow any local reuse guidelines.
Why is it suitable for these systems?
✓ Why it works with these systems
✓ Phosphate-free, chlorine-free, and bleach-free. None of the common ingredients that disrupt septic and greywater systems.
✓ Low in sodium, so it won't harm the beneficial microbes that keep a septic tank working.
✓ Used as a spray pre-treat, so only small amounts reach the outflow per wash.
✓ Readily biodegradable ingredients that break down rather than accumulating.
How do I use it with my system?
✓ Normal use
Spray the stain with Stain Remover, wait 5 to 10 minutes, then wash as normal. Use only what you need. Overdosing increases what reaches your outflow without improving stain removal.
✓ Disposal
Use up any leftover product on laundry jobs first. If disposal is necessary, dilute 1:10 with water and pour down the sink with the tap running. Don't tip undiluted product down the drain at once.
⚠ Greywater on edible plants
Greywater reuse rules vary by state, council, and water authority. If you irrigate with greywater, particularly on edible plants, check local guidance before assuming it's OK.
If you have a specialised treatment setup, your service provider may have additional guidance worth following.
✓ Good to know
✓ Always follow garment care labels and your machine's instructions
✓ Use at full strength on stains. Don't dilute the product itself.
✓ Suitable for standard residential septic and greywater setups at normal household use levels
Spray-on pre-treat for stubborn stains. Spray, wait, then wash.
New at Koh?
Stain Remover Starter Kit pairs Stain Remover with the Foaming Spray Bottle for targeted application.
Koh Perks · earn points on every order
Earn points on every purchase, refer a friend, and redeem for discounts on your next order. Find all the ways to save in one place.
Browse all Stain Remover articles
Last reviewed: May 2026
Chat with ROS-E
ROS-E handles most questions in seconds, 24/7.
Prefer a human? Just ask. If ROS-E can't answer, the rest of our team will step in. We usually reply within 1 to 2 business days.