- Water Guide basics: Each purification tool targets specific contaminants — UV lamps kill microbes, filters remove waste, minerals, and physical debris.
- High-Quality Water: Reachable via water purifier, UV lamp + filter combo, gutter tilapia, hydra weed, or a moisture farm at quality 100.
- Pure Water: Only two confirmed methods — water purifier at quality 100%+ or moisture farm at quality 150+.
- Selling tip: Display two bottles of spring water (or 365+ value) to attract the water stockpiler buyer from day 14.
How Water Purification Works
Probably Stolen's water guide starts with one core principle: the game mimics real-life purification, so every tool has a specific job. No single filter does everything (except the water purifier machine), and understanding which contaminant each device removes is the difference between stagnant base water and a profitable pure water operation.
The four contaminant types and their counters:
| Contaminant Type | Removed By | Not Removed By |
|---|---|---|
| Microbes | UV lamp, water purifier | Water filter |
| Organic waste | Water filter, water purifier | UV lamp |
| Minerals | Water filter, water purifier | UV lamp |
| Physical debris | Water filter, water purifier | UV lamp |
Video Highlights:
- Turn faucet rust water into high-quality water overnight with a water purifier
- Combine a UV lamp and pitcher filter on scavenger-purchased base water
- Hit moisture farm quality 150 for daily pure water production
- Use spring water bottles to trigger high-paying stockpiler buyers
Running base water through only a filter leaves the microbes behind — the water stays base quality. You must pair the filter with a UV lamp (or use a purifier machine) to reach high-quality water.
Four Ways to Make High-Quality Water
There are several routes to high-quality water, and each suits a different stage of the game. Pick based on the resources and machines you already own.
| Method | How It Works | Speed | Best For |
|---|---|---|---|
| Water purifier machine | Place rust water in overnight | 1 night | Early game, effortless |
| UV lamp + water pitcher filter | Lamp kills microbes, filter strips the rest | Fast | Purchased scavenger base water |
| Gutter tilapia (RAS) | More tilapia = faster cleanup in the recirculating aquaculture system | Slow, scales | Passive long-term setups |
| Hydra weed | Plant in the old hydroponic system; each growth cycle cleans water | Multiple cycles | Free, hands-off |
| Moisture farm | Generate water directly at quality 100+ | Daily output | Late-game automation |
UV Lamp Route
- Kills microbes only Works on purchased base water Cheap and reusable
Tilapia Route
- Scales with fish count Check progress with aqua scan Fully passive over time
Hydra Weed Route
- Found in old hydroponics Converts rust water to base, then high-quality Costs a little water per cycle
Scavenger-sold base water has a mixture that responds perfectly to the UV lamp + filter combo. Homemade base water may take a different path depending on how you made it, so test with the aqua scan before committing.
Making Pure Water: Step-by-Step
Only two machines can produce pure water, and both depend on machine quality. The water purifier needs quality 100%+ to reach its max purity of 99.9%, while the moisture farm needs quality 150+.
Upgrade machine quality
Install refinement modules into your water purifier or moisture farm to raise quality past the thresholds (100% purifier / 150% farm).
Expand your module slots
Use up to two expansion kits per machine to unlock extra module bays, then fill them with quality, performance, or efficiency modules.
Load your water
Pour base or high-quality water into a jug and place it in the purifier, or let the moisture farm generate water daily.
Wait one to three nights
A fully charged purifier triggers a full day cycle per charge. A jug of rust water to pure takes about three nights.
Test and bottle
Use the aqua scan to confirm 99.9% purity, then bottle and store it for sale.
With a refinement module pushing a moisture farm from 55% to 179% quality, output jumps to roughly 578 ml of pure water per day — a reliable passive income engine.
Storage, Expansion, and Selling Strategy
Pure water is only profitable if you can store and sell it efficiently. Water tanks matter more than most players expect once daily production ramps up.
| Asset | Details | Priority |
|---|---|---|
| Water tank | Up to 50,000 ml capacity | ★★★★★ |
| Expansion kits | Two per machine for extra module bays | ★★★★ |
| Efficiency modules | Lower energy cost of machines | ★★★ |
| Performance modules | Faster/more thorough purification | ★★★★ |
| Spring water bottles | Trigger stockpiler buyers | ★★★★★ |
Display two bottles of spring water on your sales stand. From around day 14 onward, this reliably attracts an upper-tier water stockpiler who buys all your high-quality or pure water for 500+ credits. One bottle comes from Natalia's questline; substitutes like a standard bottle of high-quality water work if the combined value exceeds 365.
Click a machine and press E or Q to rotate it, right-click to flip it. Useful when squeezing purifiers and tanks into a compact water workshop.
Water Operation Milestones:
- Purify first bottle of high-quality water
- Install a 24,000 ml water tank
- Reach water purifier quality 100%
- Hit moisture farm quality 150 for daily pure water
- Trigger the stockpiler buyer by day 14
- Max a water tank at 50,000 ml
FAQ
Q: Why won't my filtered water become high quality?
Water filters only remove organic waste, minerals, and physical debris. If microbes remain, the water stays at base quality. Run it under a UV lamp first (or afterward) to complete the purification.
Q: What is the fastest way to make pure water in this water guide?
Use a water purifier machine raised to quality 100% or higher. It purifies to 99.9% (pure) overnight per jug, and a fully charged machine can trigger a full day cycle instantly without sleeping.
Q: Can the moisture farm make pure water?
Yes. Raise its quality to 150 or above with refinement modules. At around 179% quality, a moisture farm produces roughly 578 ml of pure water per day passively.
Q: How do I attract rich water buyers?
Place two bottles of spring water on your sales stand — or enough water to exceed 365 combined value. From about day 14, this draws the water stockpiler buyer who purchases your entire high-quality or pure water stock for 500+ credits.