I was intrigued by ammonia electrolyte proposed here then by Aluminum decomposition ..

And I did my own modest research.

Ammonia looks to be interesting additive to refill water - it works in almost system. Gases are no longer breathable but at least the NH3 evaporated will be a good Oxygen consumer and that can enhance the end results.

Is good also to lower the freezing point of water.

Aluminum was good as electrode in AC.

If the electrolyte is not corrosive to Aluminum ( like mild Borax solution ) then Aluminum become sort of diode and block the current on one phase but release Hydrogen on the other phase. Interesting ..I get the "foam" like in Meyer or replica systems but was still under Faraday law: more current   - more gas.

I used 220 V - 50 Hz. Maybe variable frequency will be better!

Aqua Ammonia and Aluminum is interesting mixture. Aqua Ammonia in certain dilution will react with Aluminum and the gases are reach in Hydrogen and NH3. The steam can be easy collected ( under some pressure ) and injected like LPG. 

Under electrolysis in a Anode - Cathode cell 

The byproduct will be captured in the recipient and recycled.

A working system can be a replaceable canister / electrolytic cell with  ammonia refill and gas collection ports.

A dual valve will push all the liquid out to refill tank  when system is stopped keeping a small quantity of dry gas inside for start.

When will have more time I will design a simple model ...

What do you think?