Questions

The format

Why do I have to buy a vessel?

Conventional shampoo is 80% water, shipped in plastic. Corneum ships only the part that does something, as a 30 ml concentrate. Vessel 01 is where you add the water. You buy it once.

How long does a refill last?

Each 30 ml refill makes 200 ml and lasts roughly two months.

How do I mix it?

Pour to collar. Fill to line. Shake once. The line is etched into the glass at 200 ml.

How it works →

Can I use my own bottle?

You can. The concentrate doesn't know what it's in. But the dose line is the point: without it you are guessing the dilution.

Is any of it plastic?

No. The vessel is borosilicate glass and 316 steel. The vial is aluminium. The mailer is paper. No tissue, stickers or sample sachets.

Why no pump?

Pumps are plastic, they fail, and they can't be recycled. Corneum pours.

The products

Where should I start?

With the concern, not the product. The range page maps each concern to one product.

Choosing →

Can I use more than two products?

We discourage it. More actives means more irritation, not more result.

Is 4% salicylic acid too strong?

Cleanse contains 4% salicylic acid. That's a clinical concentration. If your scalp is already irritated, start with Cleanse Mild or you will make it worse.

Cleanse Mild →

Will Density make my hair thicker?

This will not make your hair thicker. Nothing makes hair thicker. It may increase the number of follicles in an active growth phase, which is a different claim, and the one we can support.

Can I stay on Reset?

No. Reset is an intensive six-week course. Six weeks, then stop. If the problem returns, see a clinician.

Orders

Does my first order need a vessel?

Yes. Refills pour into Vessel 01, so a first order has to include one.

Can I order refills without a vessel?

Once you have bought a vessel, yes. Accounts aren't part of this site yet, so a past order is only remembered in the browser you ordered from.

Is payment taken?

No payment is taken on this site.

How do refills arrive?

In a flat paper sleeve, slim enough to post through a letterbox. No courier, no box.

Still asking

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