Oasis 167mg Tablets review
Oasis 167mg Water Purification Tablets (100)
By Tom Calder
The high-volume version of a long-trusted tablet: one 167mg Oasis tablet treats 20 litres in about 30 minutes, so a pack of 100 covers up to 2,000 litres. It's the sensible choice for whole-household resilience rather than a single bottle, and it stores for years.
- Best for
- Disinfecting larger volumes at once: a stored water container, or the household's drinking supply during a mains outage or boil-water notice.
- Skip it if
- You only need to treat a bottle or two on the move
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Researched, not used. We haven't used this product. This review is built from the maker's specifications, owner reports and our own sizing.
What we like
- One tablet treats 20 litres in about 30 minutes, so a pack of 100 covers up to 2,000 litres
- Chlorine chemistry that kills bacteria and viruses, with far less aftertaste than old-style iodine tablets
- Strips of 10 in a resealable bag, with a four-year shelf life
Worth knowing
- Chlorine tablets don't reliably kill Cryptosporidium and work less well in cloudy water, so filter silty or surface water first
- Dosed for containers, not a single bottle: one tablet in a litre is wasteful and tastes strongly of chlorine
Out of stock when we checked: our alternatives
Closest in size first, then by our score. None of them was showing out of stock when we last checked.
Best for A compact chemical backup for a grab bag, treating clear water on the move.
as of 2 Nov 2026, 13:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.
Best for A compact, long-shelf-life water backup for a grab bag or travel where you cannot boil or filter.
as of 2 Nov 2026, 13:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.ⓘ As an Amazon Associate, PreparedBritain earns from qualifying purchases. We may earn a commission when you buy, or a fee when you request a quote, through our links. When two products are close, commission can decide which one we pick. A clearly better product always wins. Amazon prices come from Amazon's own product data and show the date and time they were retrieved. Prices at other retailers are checked by us, less often. Prices and stock can change at any time, so always check the retailer's price before you buy.
Our review
Oasis 167 mg tablets are the bulk-water size: each one disinfects 20 litres of clear water in half an hour, which makes 2,000 litres from the full pack of 100. They suit a household that stores water in jerrycans or needs to treat a container at a time during an outage. They are a disinfectant, not a filter, and not the right size for a single bottle.
What they are
Each tablet holds 167 mg of sodium dichloroisocyanurate (NaDCC), a chlorine-releasing compound, and is dosed to give 5 parts per million of available chlorine in 20 litres. The pack is 100 tablets in ten foil strips of ten. The instructions, as reproduced by UK supplier EVAQ8, are to add one tablet to twenty litres of suspect water and leave it for 30 minutes before use; the same page says a tablet treats 20 to 25 litres of clear water, or 2,000 to 2,500 litres a pack.
We couldn't find a manufacturer's page for this pack that we could read, so the figures here come from that UK supplier's listing. Check the label on the pack you buy, because chlorine tablets come in many strengths.
How to use them
Fill the container, add one tablet per 20 litres, close it, swirl, and wait the full 30 minutes. Use clear water. The US Centers for Disease Control advises filtering cloudy water through a clean cloth, paper towel or coffee filter before treating it, because sediment shields germs from the chlorine. The government's Be Ready advice says to follow the instructions on the product label, as tablets come in different strengths, and that most alternative water sources will need filtering before tablets are used.
The 20-litre dose is the reason to buy this pack. A 20 or 25-litre jerrycan takes one tablet, which is far simpler and cheaper than counting out single-litre tablets. Our guide to storing emergency water covers containers and rotation.
What they can't do
Chlorine does not remove mud, chemicals, fuel or heavy metals. The CDC also says chlorine tablets kill most germs but will not kill Cryptosporidium, a chlorine-resistant parasite. If that is a risk, use a fine filter as well, or boil the water. If your water company issues a boil water notice, follow its instructions rather than relying on tablets.
The tablets are too strong for a single bottle: one in a litre would be twenty times the intended dose. Keep smaller tablets for the grab bag.
How they compare
On our purification tablet comparison, Aquatabs 67 mg treat 10 litres each, a middle size for a bucket or a smaller container. The one-litre Aquatabs, Oasis's own single-litre tablets and Katadyn Micropur Forte suit bottles. Pyramid's BioX Aqua tablets use chlorine dioxide, which the CDC says will kill Cryptosporidium if the label's instructions are followed.
Our verdict
The sensible pack for a household that keeps stored water in large containers, or that might need to make tap or rain water safer by the jerrycan. Pair it with a filter for cloudy water, and keep a few one-litre tablets alongside for bottles on the move.
A researched review, built from the maker's specs, manual and UK listings; facts checked 2 Nov 2026. Sources: EVAQ8: Oasis water purification tablets 167mg NaDCC x 100 (UK supplier); CDC: Making water safe in an emergency; GOV.UK Be Ready: water supply interruptions.
Who shouldn't buy this
You only need to treat a bottle or two on the move: a one-litre tablet is far less wasteful. If Cryptosporidium in stream or flood water is the worry, pair tablets with a physical filter or choose a different method.
Key specs
| Treats per tablet | 20 litres |
| Active agent | Chlorine (167mg active ingredient per tablet) |
| Pack size | 100 tablets (strips of 10) |
This is a Researched review: we haven't used this product. We check every specification against at least two independent sources, re-check the UK price on a schedule where we can track it automatically, and say plainly who it isn't for. Commissions never change a rating.
Questions
How much water does one Oasis 167 mg tablet treat?
One tablet treats 20 litres of clear water, giving 5 ppm of available chlorine, according to the instructions reproduced by UK supplier EVAQ8, which also quotes 20 to 25 litres. The 100 tablets in the pack treat 2,000 litres between them.
How long do I wait after adding an Oasis tablet?
Leave the water for 30 minutes before using it. Filter cloudy water first, through a clean cloth, as the CDC advises.
Do Oasis tablets kill Cryptosporidium?
No claim is made for it, and the CDC says chlorine tablets will not kill Cryptosporidium. Use a fine filter as well, boil the water, or use a chlorine dioxide product as its label directs.
Can I use Oasis 167 mg tablets in a water bottle?
Not sensibly. Each tablet is dosed for 20 litres, so it is far too strong for a single bottle. Keep one-litre tablets for bottles and use these for jerrycans and large containers.
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