I almost walked this path, but ended up buying a Sparkel https://sparkel.com/ https://sparkel.com/ -- it creates CO2 on the fly, using sachets of citric acid an

I almost walked this path, but ended up buying a Sparkel https://sparkel.com/ https://sparkel.com/ -- it creates CO2 on the fly, using sachets of citric acid and sodium bicarbonate. It's pretty easy to use, seems pretty robust, and my use of it has lasted much longer than my use of Sodastream which I never managed to keep up the habit of swapping tanks and so on.