Water in Probably Stolen: Cyberpunk Shopkeeper Sim comes in six purity grades, and customers care which one you sell them. Clean water is something you make yourself, and the tools you use decide how clean it gets.
Quick answer: Drop Water Purification Tablets in and pour the water through a Water Pitcher with a Water Filter to reach Basewater or High-Quality. For Pure Water (99.9%+), you need the Water Purifier machine with Quality modules.
The Water Purifier rules below apply as of version 100-REV3 (the 28 October 2026 patch). That patch reworked how the machine removes contaminants and added a Max Purity line to its tooltip.
Water grades in Probably Stolen
The Water Trading Manual sorts all water by purity. The grade sets what the water is safe for and who will buy it.
| Grade | Purity | What the Water Trading Manual says |
|---|---|---|
| Pure Water | 99.9%+ | Very expensive, used in hospitals and labs |
| High-Quality | 99%–99.9% | Upper Levels standard, safe to drink and cook with |
| Basewater | 98%–99% | Lower Levels standard, risky over long use |
| Ghostwater | 96%–98% | Looks clean, unsafe to drink unfiltered |
| Rustwater | 90%–96% | Dangerous to drink, visible by eye |
| Gutterflow | Under 90% | Toxic, visible by eye |
Ghostwater is the tricky one. It can’t be told apart from better water by sight, which is why passing it off as Basewater is a common scam. Selling large volumes of it is a crime. A Water Testing Strip is a cheap way to check purity, and the AquaScan (base value 200) shows which impurities are in the water.
Water Purification Tablets, Water Filters and other tools
Every method only removes certain types of contaminant. If repeating a method stops raising purity, that method can’t remove what is left, and you need a different tool.
| Item | Base value | What it does |
|---|---|---|
 Water Purification Tablet | 6 | Removes most microbial contaminants, some chemical ones |
 Water Filter | 25 | Filters water as it is poured into a Water Pitcher |
 Advanced Water Filter | 350 | Pitcher filter that recovers 50 durability each day |
 Hydroreed Filter | 20 | Removes certain contaminants in a filter system |
 Hydroreed Seed | 20 | Crop that filters the water surrounding its growth |
 UV Lamp | 150 | Kills bacteria and other microorganisms |
 HydraTech Micro Water Purifier | 325 | Raises any container’s contents to Basewater |
Tablets work on chemical contaminants first, then microbial ones. A single tablet handles a large bottle of Rustwater, while dirtier water can take several. Tablets also come as a Bottle of Water Purification Tablets.
The Water Filter goes inside a Water Pitcher and cleans water as you pour it in. It removes impurities, microplastics and organic waste, but its durability runs out, and its item text warns it is “Ineffective above a certain threshold.” Using tablets and a filter together brings most water up to Basewater. Depending on where the water started, it can reach High-Quality.
Hydroreed Seeds have the Purifying trait, which cuts each contaminant by 10% nightly, up to a maximum purity of 95%. The HydraTech Micro Water Purifier is a Luxury Item; it raises the contents of a container to Basewater and loses 1 durability for every 100 ml. Kotton Fabric is too coarse to filter water.
Gutterflow wears out filters fast, so the manual advises against cleaning it with basic methods. Gutterflow is a job for the Water Purifier.
How to get the Water Purifier and water supplies
Start by unlocking Water Trading. In Wild’s Network, go to Water > Water Trading, which costs 300 favor. You get a Water Trading Starter Kit right away, and a Water Trader starts visiting the Store. The kit contains:
- The Water Trading Manual
- A box of Water Testing Strips and a box of Water Purification Tablets
- A Water Pitcher and a Water Filter
- A Water neon sign
- A part-used HydraTech Micro Water Purifier
The kit doesn’t include the Water Purifier itself. Once Water Trading is unlocked, there are two places to buy one:
- Dr. Jackson: A Water Purifier, along with its instructions, is available in his machine stock only while you don’t own one.
- Retired Water Merchant: visits on Wednesdays (Day 3, 10, 17, 24 and so on) and opens with “Hey, I got some stuff I don’t need anymore.”
The Retired Water Merchant’s wares include a Water Purifier, Moisture Farm, Water Testing Strips, Water Purification Tablets and Water Filters. He also comes by if you picked the Water Merchant specialization. Its starting supplies are a Water neon sign, Bottle Printer, bottles, a Jug of Water, Water Pitcher, HydraTech Micro Water Purifier and Water Trading Manual. As of 100-REV3, the Water Purifier has a base value of 250 and occupies a 3 x 4 inventory space.
Wild’s Network also sells Gutterflow On Tap for 250 favor, which gives unlimited Gutterflow whose purity changes daily, and Rustwater On Tap for 350 favor. The Moisture Farm (base value 350) makes water from the air into a container you provide. During the Water Supply Crisis station event, water prices go up. A Sealed Water Ration (Standard) shows an Est. Value of 45 against a Base Value of 30, and its text reads “Can be poured into a liquid container for 750ml of Basewater.” We saw that on Day 26 of our run.
That makes the crisis days a good time to have clean water in stock.
How to use the Water Purifier (version 100-REV3)
The Water Purifier uses reverse osmosis to clean water inside a container you give it. The machine window has a power slot, a module grid, a container slot and a note slot. It works overnight, so load it before the day ends.
It is one of the machines in our crafting recipes by machine list.
What the Water Purifier does each night
- Contaminant removal comes from a single shared allowance, and a larger container gives that allowance more capacity.
- The allowance is far greater for heavily contaminated water: very dirty water gets about 20 times as much as water at 98% purity or higher.
- Performance modules increase the budget.
- It clears the biggest-particle contaminants first. Minerals, Chemical Contaminants and Heavy Metals go last.
- Removed contaminants turn into water, so the volume doesn’t drop.
- If the water has reached its cap and nothing is removed overnight, the purifier consumes no power.
Because the nightly budget is so much bigger for heavily contaminated water, the machine does its fastest work on Gutterflow and Rustwater. The last steps toward the cap go slowest.
How to get Pure Water with Quality modules
The manual spells out the requirement: a dedicated Water Purifier fitted with the proper Modules is needed to produce Pure Water. With no Modules, the machine tops out at 99%, making High-Quality the highest possible grade. Quality bonuses increase that limit:
| Quality bonus | Max Purity | Best grade |
|---|---|---|
| None | 99% | High-Quality |
| +15 | 99.15% | High-Quality |
| +25 | 99.35% | High-Quality |
| +50 | 99.65% | High-Quality |
| +75 | 99.8% | High-Quality |
| +100 | 99.9% | Pure Water |
| +200 | 100% | Pure Water |
Aim for a Quality bonus of at least +100. The machine’s tooltip should read “Max Purity: 99.9%” or higher. Once “Contaminant Removed (Last Night)” drops to nothing, the water has reached that cap. Confirm the result with a Water Testing Strip or an AquaScan before you sell.
Pure Water isn’t suitable for every buyer; some Lower Level citizens and Scavengers won’t purchase it. For wine, the BloomBerry Identification recommends High-Quality Water or Basewater, since fermentation requires minerals that Pure Water doesn’t have. A Vending Fountain can dispense from a Water Purifier or Moisture Farm tank, but its offerings are limited to Basewater, High Quality Water and Pure Water.
Who buys clean water
The Water Trading Manual has a few rules about water buyers. Scavengers are usually too poor to carry a Water Testing Kit, Tourists and Upper Level Citizens rarely test what they buy, and customers who want a lot of water usually carry a testing kit.
Some customers ask for clean water outright. On Day 27 of our Mark Up run a customer called Sick Scav came to the window in a gas mask: “Clinic said I’ve been drinking too much bad water.”
He wanted High-Quality water and had 175 credits to spend. We had no water on the counter, so his panel read Not interested for everything:
Tips
- Test before you sell. A Water Testing Strip is cheap, and selling mislabeled Ghostwater in large volumes is a crime.
- Use tablets and a filter on Rustwater, and save the Water Purifier for Gutterflow and for the last step to High-Quality or Pure Water.
- Check the machine’s “Max Purity” tooltip line before you buy more Quality modules: below +100 the cap stays under Pure Water.
- A purifier at its cap uses no power that night, so you can leave a finished bottle in it.
- For BloomBerry wine, use High-Quality Water or Basewater, not Pure Water.
Related guides: the items list with every base value, the vending machine guide, hydroponics and Hydroreed and the complete Probably Stolen guide.
