do co2 systems like this work well?

I've never even seen a device like this before. In theory it would work pretty well, but would probably use a lot of electricity to separate the bonds in water molecules.
It's up to you. Hopefully someone could provide more/better information than I can.
 
I have no idea whether this device would work or not, but I noticed that it's been up for bids for a few days with 0 bids.
Len
 
The system is describing the same process used in the new Carbo Plus systems (do a web search). I've never used one but them seem to work as claimed. I don't recognize the manufacturer of the one you mention though. The details are that the water has to have a high enough kH (add baking soda) for the electrolysis to occur. The carbon plate elements are installed in the tank and give off a "mist" of CO2. They are simpler to use then compressed CO2, but they aren't designed to be used with a reactor and the plates which are about $30.00 need replacing about every 4 mo. So with in a year it will probably cost more then having purchased a pressurized system. Of course the plates can be delivered to locations were $5.00 CO2 refills aren't available.
 
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