Frequently Asked Questions

How does Kishu Charcoal work?

Activated charcoal naturally bonds with toxins. This is why it is used, in some form, in almost every water filtration system in the world. In municipal water systems, various additives (chlorine, for example) are also included in the treatment of water. And some municipal systems are not as rigorous as they could be. It is because of this that consumers are wary of their water source, want to filter their water, and is probably the reason you have happened upon this website!

How do I use Kishu Charcoal? Is it complicated?

Kishu could not be easier. Simply place your stick of Kishu in any vessel and add tap water. Kishu begins working immediately. It does not need to be removed.

How do I care for Kishu Charcoal? 

Kishu needs no special care, but boiling the stick once a month keeps its exterior pores open. Completely submerge your Kishu stick in a shallow pan of water and bring to a robust boil for 5 minutes. Empty the pan of water and allow it to dry for 30 minutes. After 4 months, it’s time to replace your Kishu stick with a new one.

Can I clean Kishu Charcoal to remove the toxins?

Kishu cannot be cleansed of toxins because they have bonded at the molecular level. Once this molecular bonding occurs, the toxins will remain attached. The toxins that have been removed will not leach back into the water.

How long does Kishu Charcoal last?

One stick lasts 4 months.

How will I know when my Kishu Charcoal is no longer filtering effectively?

After 4 months, you will notice that your water no longer has the distinct, bright, fresh taste you have come to love.

So, do I have to throw it out then?

No! Kishu has many uses in its second life as a deodorizer in the refrigerator or other places where odors are present. Because it is biodegradable, it can also be mixed with soil in the garden to create bio-char, or used in the bottom of potted plant for drainage.

Please share your own ideas for second-life uses of Kishu on our Facebook page.

Does Kishu Charcoal ever break down or dissolve?

Kishu never dissolves. A little flaking may occur, but this is NOT AT ALL harmful and will not affect the filtering process.

If you use Kishu Charcoal with plastic containers, will it draw anything out of the plastic? 

As plastic can leach harmful chemicals, we do not suggest using plastic. However, BPA-Free plastic is the safeest we are aware of. We recommend glass or metal containers.

Will Kishu Charcoal remove or reduce fluoride?

The fluoride molecule is extremely small, so Kishu is not able to bond with it in a robust way, unlike many metals (see our Science tab) for which Kishu has an afinity.

What size of Kishu Charcoal should I purchase? 

If you visit our SHOP page, you will find several sizes: a slender stick for water bottles –

Kishu To Go; a larger stick for pitchers and carafes – Kishu Regular; an extra large stick for any vessel larger than 2 quarts – Kishu X-Large.

I like to drink my water with fruit. Is it okay to put the Kishu stick in with fruit water?

The fruit fragments will clog the pores of the stick, so we do not recommend using it in that manner. Intead, just add Kishu filtered water to your fruit.

Where can I purchase your product locally?

Our distribution is growing across the U.S. and Canada. However, if you know a local store that you think would be a good fit, please ask them to carry Kishu Charcoal (there is an order form for stores under our WHOLESALE tab)! Otherwise, you can buy directly from us on this website. We are also available on

Tell me about the packaging.

We are so proud of our packaging. We took special care and research to create a completely biodegradable package: our label is made from paper that is FSC® Certified, SFI® Certified Sourcing, and Rainforest Alliance Certified™ and printed using the most environmentally friendly process available. The clear sleeve is made from wood pulp and is completely compostable.




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