Igor Stropnikvideo
Watermaker - Sea made drinkable
July 5, 2025 · 9 min · 95K views · Adriatic Sea, Croatia
What this video covers
A manual hand-pump watermaker is tested on the Adriatic Sea off Croatia, producing desalinated drinking water from seawater.▶ 0:00 The unit costs €250 and uses a reverse-osmosis membrane to separate H2O from salt, brine, bacteria, and viruses; the brine exits through one hose while fresh water exits through a second.▶ 8:13 First use requires a five-minute flush to clear membrane preservative, which causes milky output.▶ 1:50 Actual output measured at roughly one deciliter per five minutes — approximately 1.2 liters per hour — well short of the manufacturer's claimed four liters per hour.▶ 3:09 A TDS meter reads 743 and 870 ppm on successive batches; anything under 1,000 ppm is considered drinkable.▶ 4:18 The water tastes fresh with a slight aftertaste.▶ 6:08 The manual pumping effort is significant: sweating starts within five minutes.▶ 1:42 For comparison, Katadyn makes a similar manual unit for around €2,000.▶ 5:07 Other survival water options discussed include solar stills and rainwater collection.▶ 5:17 The reverse-osmosis principle is the same used in electric watermakers on cruising boats, which can produce 50–1,000 liters per hour. Real-world output is far below spec, but the unit can sustain life in an emergency.▶ 7:42
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