It's trivial to separate water with heat or power. We have both in abundance with fusion power plants.
Fuel processors or purifiers purify the hydrogen by removing impurities, i.e. other elements such as the extra oxygen or nitrogen collected from gas giants or oceans.
Presumably the life support system contains dedicated CO2 scrubbers.
I guess the internal air and water can also be flash-heated to remove any biological pollutants.
Use waste heat from the power plant to power chemical vapor deposition sequestration of carbon as diamond dust. Sandcaster refractive loads on the cheap?
Wow. Just the number of creative solutions tells me that this sort of material is EXACTLY what the players should be coming up with on the fly, rather than being codified in rules.
Wow. Just the number of creative solutions tells me that this sort of material is EXACTLY what the players should be coming up with on the fly, rather than being codified in rules.