The molecular hydrogen is generated by a reaction between the elemental magnesium of the O-Dobi media and water.
H2 is being generated while the Ultrastream is at rest, and accumulating to its maximum even before you pour a glass. This means that the water (approx.250ml) inside the UltraStream is hydrogen enriched and just waiting for you to pour. As new water enters the UltraStream the process of enrichment begins again.
We’ve measured output at 1.2ppm here at Alkaway but we have to say that it always depends on the suitability of your source water, so we can’t promise a particular number. We have found that softer (more acidic) waters generate more h2 than more alkaline input waters.
H2 production will slowly reduce over the life of your filter as calcium accretes on the O-Dobi media. That’s one reason we use KDF media. As well as removing heavy metals and neutralising bacteria, KDF also neutralises excess hardness in input water – before the water reaches the O-Dobi.