Augeo Clean Multi vs DPG: Which Reed Diffuser Base Is Better?

Most reed diffuser bases are DPG, a petroleum solvent that barely evaporates. Augeo Clean Multi is the plant-derived base the better diffusers use. What the difference is, how much it matters, and how to mix it.

If you have ever made a reed diffuser that smelled wonderful in the bottle and of almost nothing on the shelf, the fragrance was probably fine. The base was the problem. The liquid that carries the oil up the reeds decides how much scent actually reaches the room, and most bases on the market are the same cheap solvent.

What a reed diffuser base does

A fragrance oil on its own is too thick to travel up a reed and too strong to sit in an open bottle. The base thins it, carries it up the fibres by capillary action and lets it evaporate from the tips at a steady rate. A good base is invisible: no smell of its own, and an evaporation rate fast enough to throw scent but slow enough to last weeks.

DPG: the default

Most budget bases are dipropylene glycol, DPG. It is a petroleum-derived solvent that has been used in fragrance for decades because it is cheap and blends with almost anything. Its weakness in a diffuser is that it evaporates very slowly. The reeds stay wet, the bottle lasts a long time, and the room gets less fragrance than you paid for. Many makers compensate by pouring in more oil, which costs more and can push a blend past its safe limit.

Augeo Clean Multi: the upgrade

Augeo® Clean Multi is a solvent made mainly from glycerin, a by-product of biodiesel production. According to its manufacturer it is about 70% renewable carbon and has a carbon footprint up to 40% lower than DPG and the glycol ethers it replaces. Three things matter in a diffuser:

1. It has almost no smell. A base with an odour of its own flattens the top notes. With Augeo the oil smells like itself.
2. It evaporates at a better rate for reeds. It lifts more fragrance into the room than DPG, which is why scent throw is the first thing people notice when they switch.
3. It is the base the better brands use. If a reed diffuser is described as plant-based and low odour, there is a good chance this is what is in it.

The safety data sheet is worth reading rather than skipping. Augeo Clean Multi is classed as a combustible liquid (flash point about 91 °C), not a flammable one, and it is inherently biodegradable. Like most solvents it is an eye irritant and it carries a reproductive-toxicity warning on its SDS, so it is for diffusers only: never on skin, never swallowed, kept away from children and pets, with spills wiped up promptly. Any honest supplier will send you the SDS when you ask.

How to mix it

We blend every Velour and Vellum reed diffuser at 3 parts base to 1 part fragrance oil (25% oil). Stir, cap it and let it rest 24 hours before adding the reeds, so the oil fully dissolves. Stay within the IFRA limit your oil supplier gives for reed diffusers; for most fine fragrance oils 20 to 25% sits comfortably inside it. Flip the reeds once a week and a 200 ml bottle lasts six to eight weeks in a normal room.

Where to buy it

Augeo is usually sold in drums to manufacturers, which is why it is hard to find in small sizes. We sell the same base we use, unscented, in amber glass from 250 ml to 5 L, shipped across Canada and the US: Reed Diffuser Base — Augeo® Clean Multi. Pair it with our weighted glass diffuser vessels, fibre reeds and any of our Nebulizing Concentrates, which are 100% pure fragrance oil and blend cleanly into it.

Augeo® is a registered trademark of Syensqo. Velour and Vellum is not affiliated with Syensqo.

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