system
Given the following post, respond as if you're commenting on Reddit:
human
[The Expanse] Where the fuck is all the water going?

Ceres is said to have had enough water for a 1000 generations, the Earth and Mars took it all. I mean, okay, I Mars took all the ice as part of a terraforming project I can see that. Removing it on mass from a central easy to get to point. Maybe Earth was using it to refill it's ships and for Luna maybe. Even still that doesn't account for, what has to be dozens of other massive asteroids and comets accost the system. 

All that history aside, the thing that bothers me the most is the seeming lack of advancement in critical recycling systems aboard ships and stations! Even today aboard the ISS there extreme little "waste water". How can it be that in the 23rd century in places where water and air are so precious that there are not extreme measures put in place to recapture all water? I just seems like ships just dump there waste directly into space.

They clearly have fusion power plants, which means... I'd assume, power is relatively cheap. They should have more than enough to collect black and gray water, sift and treat the water, then boil and re-condense it. Especially on Earth where sea levels have risen by 50ft, to the point where they are drowning in sea water!
gpt
The recycling equipment that they have the Expanse is insane compared to today. No way in hell could we keep several stations of large populations self-sufficient with our current engineering (although there are possible solutions but nobody can try them out). It's like the difference between looking at a Roman city's sewage system compared to ours. 

As for where all the water is going, it's all going to the Earth (massive lifespan + overpopulation = nightmare logistics) and the Mars terraforming, which Mars needs a HUGE amount of water for. In the end, they don't give a shit about the Belters, so they aren't willing to share any more water than they have to. 

Think of it in today's terms. We 'buy' quite a few resources from Africa, where people are truly poor, and yes there are people who care about poor African countries (Somalia, Nigeria) but most people don't care, or only pretend to care (like the UN in The Expanse), because they have their own problems. The only people who benefit in Africa are the corrupt dictators who get all that Western money while people starve. The same dynamic is repeated in the Belters (poor) and the Governers (of the stations). Notice how the Governers had that massive garden? They aren't dying from lack of water.