Probably Stolen how to make pure water comes down to one machine and a lot of patience: the reworked Water Purifier can lift high-quality water to pure grade overnight, but only after the water is clean enough to start with. This page walks the route step by step from Owlie's Water Trading Made Easy guide on Steam, which was updated on November 1, and from the developer's hotfix notes. It does not repeat the basic loop; for that, read the Probably Stolen water guide.
Probably Stolen how to make pure water: the short route
Customers buy water by grade. A demo-era guide by The Exceptional Fisherman lists pure water as 99.9% and above, worth double the base price, and high-quality as 99 to 99.9%. Owlie's guide adds the detail that matters for planning: 99.00% purity is the goal for high-quality water, and any purity above that does not change its sale value. Pure water is therefore a separate project, not a longer version of the first one.
- Get the water to high-quality first (pills, filter, softening).
- Run a full container of 99.00% high-quality water through a Water Purifier with 100% or better quality.
- Leave it for a night and test it; the guide's own test turned a 6L jug at 99.00% into 99.90% pure water in one night, using a purifier with 103% quality and 28% performance.
The author says the purifier could not do this before its mechanic changed, and calls the result easy now. The developer's hotfix 1.0.0.2 reworked the purifier's logic, so older guides may disagree.
Step one: clean the water to high-quality
Filters no longer remove microbes in 1.0, according to the guide, so pills and light do that job. Use each tool for what it removes:
| Tool | What it removes |
|---|---|
| Water purification tablet | All microbes, and chemical contaminant down to 0.71%; each tablet removes 80 ml of contaminants |
| UV lamp | All microbes; saves tablets but does not replace them |
| Water filter in a pitcher | Filterable contaminants; it cannot remove chemical or heavy metal contamination |
| HydraTech Water Purifier | All contaminants equally, up to basewater quality |
| Water Purifier machine | A little of every contaminant each night; best on heavily contaminated water |
The guide's rustwater route is: add one tablet per 2L (two for a 6L jug), leave the container in a powered Water Purifier for one or two nights if it is 2L or three nights if it is 6L, pour the result through a pitcher with a filter, then test. Its measured run on 6L of rustwater with two tablets went from 95.50% purity to 97.00% after one night, 98.15% after two and 99.00% after three. If you land on basewater, add another tablet, use the UV lamp or give it one more night. The machine always leaves a little chemical contamination.
Dilution and other routes to pure water
Dilution stretches your supply. Any purity above 99.00% is excess you can spend: 1L at 99.50% mixed with 1L of basewater at 98.50% makes 2L at 99.00%. Pure water is the best thing to dilute with, the guide says, because it gives the most extra volume.
The same author tested organic cleaners that stand in for the machine. Six adult Gutter Tilapia in a 12L tank of rustwater with five tablets reached high-quality water by the third night, and Hydroreed reached it by the second night in a 6L test, then plateaued near 98% total. The Evaporator pulls out 300 ml a night but only returns the water if its quality is raised with modules. A HydraTech method that turns nutrient tablets or rat droppings into water is described too, and the author warns it might be an exploit, so we do not recommend it. See the Aquafarmer scenario for the fish side.
Costs and prices to recheck in game
Plan the money first: Probably Stolen how to make pure water needs a purifier, batteries and tablets before it pays. Prices in the guide predate some hotfixes, so use the patch notes first. Hotfix 1.0.0.2 cut the Moisture Farm from 650 to 350 and the Water Filter from 50 to 25, and hotfix 1.0.0.5 cut the Water Purifier from 300 to 250. Owlie lists the machine at 345 from the retired merchant and 375 from Dr. Jackson, which is older than that price cut, and puts the Rustwater tap upgrade from Wild at 550 in favors and credits. The author also advises against buying a Moisture Farm in the early game and suggests a Water Purifier or the advanced filter first. All changes are logged in Probably Stolen patch notes.
Once you can make pure water, a full 6L jug of high-quality water on display can attract the upper-level water hoarder after the first two weeks, according to the guide. Start with the Water Merchant scenario if you want the kit built for this, or the Hydroponic Farmer scenario if you need clean water for crops. Chemists need it too: see the Probably Stolen Chemist page.
Probably Stolen How to Make Pure Water FAQ
What counts as pure water in Probably Stolen?
A demo-era guide lists pure water at 99.9% purity and above, and high-quality water at 99% to 99.9%. The developer has not published 1.0 grade thresholds, so treat these as the best available numbers.
Can the Water Purifier make pure water?
Owlie's guide says yes after the mechanic change, if the purifier has 100% quality or more. In the test, a 6L jug of 99.00% water came out as 99.90% pure water after one night.
Why does my water stop at basewater?
Chemical and heavy metal contaminants cannot be filtered out, so a little remains and keeps it just under 99%. Dilute it with high-quality water, or add tablets and run it through the purifier for more nights.
Is pure water worth more than high-quality water?
A demo-era guide says pure water sells for about double the base price and high-quality for about half more. The 1.0 modifiers are not published, and the Probably Stolen water guide keeps the table with its caveats.