If you don't plan to drink the water, that only affects the final water.

The filter, (the stainless steel tank), should always have distilled water but only needs changed about every 8 hours of use.

The humidifier should always have distilled water but, if you are not breathing or drinking the final water can be 'clean' water (tap or spring) NOT mineralized!

The final bubbler should always have distilled water. Even if you are not drinking it immediately, you can then drink it later. This is the drinking water and some people have strongly held belief that mineraized water is what they should drink so that's what they use in the bubbler... It's your choice.

Your Berkey water sounds okay for the final bubbled water if you are not drinking it, but as I said, if you are not drinking it, you can just keep bubbling it until you ARE ready to drink it

Here in Europe they distinguish between distilled water for irons, humidifier etc. and the other type for medical use, but this one I have to buy in the pharmacy (and it cost much more). Is the "normal" distilled water good enough, also for making with the bubbler the water to drink?

Yes, the normal distilled water should be good enough. I’d use the pharmacy grade if I could afford it but if money is an issue then the regular is acceptable.

The purer you can make the water, the better everything will perform. But the difference would be hard to measure except over a long period of time.

More sludge will form in the machine with less pure water resulting in need for more frequent clean outs. The less pure water won’t scrub lye quite as well as pure water, (in the filter and humidifier). The less pure water won’t, (in my opinion), be quite as healthy to drink, due to non-bio-available impurities.

Another option is to buy a really good water distiller. I’d recommend one that has a ‘pre heat’ cycle, which gets rid of ‘light’ contaminates before the regular distillation starts. Here’s the one I use: https://purater.com

The problem is that your well water tests high because of impurities. Just because the pH is high doesn't make the water healthful. It needs to be high because of hydrogen, not minerals.

Lye makes a pH of 13...Would you drink lye water? So no, my recommendation is drink ONLY distilled water that has been bubbled with BG.
http://www.eagle-research.com/cms/faq/browns-gas/browns-gas-health-enhancement/should-i-drink-distilled-water

I now recommend water changes in the filter and humidifier after every 8 to 10 hours of use.

I am concerned about safety with the AquaCure. in the manual you say that it should be operated in an environment temperature 65 to 75 degrees Fahrenheit. It gets hot here and the main room I live in can get over 90 in summer. Can the device spontaneously combust even when not in use?

No, 90°F is OK for that, it will not self-explode even in higher temperatures. The main reason I put in the temperatures is to keep it out of FREEZING temperatures, which would damage the machine.

Should I keep my AquaCure in a cool room, only?

I wouldn’t operate it at greater that 90°F because fittings inside might start to leak.

Also known as Sodium Hydroxide, NaOH and caustic soda. This is an inorganic chemical at minimum 99% pure. It is a white solid and highly caustic metallic base and alkali salt. Sodium hydroxide is soluble in water, ethanol and methanol.

This alkali is deliquescent and readily absorbs moisture and carbon dioxide in air.

In Soap Making: Lye is mixed with water to create a lye solution. Lye solution, when mixed with fats and oils, will cause a chemical reaction called saponification (fancy for soap). The result of saponification is beautiful handmade soap.

In Food Prep: Food uses of sodium hydroxide include washing or chemical peeling of fruits and vegetables, chocolate and cocoa processing, caramel coloring production, poultry scalding, soft drink processing, and thickening ice cream. Olives are often soaked in sodium hydroxide for softening; Pretzels and German lye rolls are glazed with a sodium hydroxide solution before baking to make them crisp.

Lye is also used in candle making and making Bio-Diesel.

In Cleaning: Industrial, or technical, grade lye is often used as a cleaner and is the active ingredient in common drain cleaners. Sodium silicate is often used as a corrosion inhibitor to prevent lye from corroding pipes while it removes the blockage. Citric acid, or other acids, are often used in coordination with lye as it creates an exothermic reaction (heat) to leave sodium acetate (a salt) and water.

An alternative, but less effective alternative is sodium bicarbonate (do NOT use sodium bicarbonate (baking soda) or sodium chloride (table salt) in electrolyzers).

You could put 10 ounces of lye in and you'll get a much more efficient production of twice the quantity of gas.
I choose to run a really lean mixture (on the edge of not producing any gas) to make the electrolyte 'safer' (less caustic), reduce foaming, and reduce gas production to a level more safe to breathe.

The gas is totally non-toxic, but has this explosion issue... So to make it non-explosive it needs to be mixed with air in a ratio that causes the final mixture to be LESS than 4% hydrogen in air.

So I run a lean electrolyte (about 1 ounce of lye per quart) to balance out all the factors. But any leaner and your gas production drops off fast.

One bottle of lye for sure and optionally (but recommended) one bottle of citric acid.

The operation manual has now been changed to match the website and if you subtract the weight of the bottle and cap you'll find it's close to one ounce of powder in each bottle.

In any case, you could put up to 4 ounces in the machine and it'd be OK, it just doesn't NEED more than one ounce.

However much lye you add, it’s recommended to add an equal amount of citric acid.

Some people try to use only citric acid as an electrolyte, because it is ‘food grade’.
Citric acid is a very poor electrolyte. It requires more than twice the voltage to puch amperage using citric acid. Citric acid works best to help mitigate the effects of a great electrolyte like lye.

He is asking me how much chemical lye he should put in it.

My electrolyzers will function with as little as 1 ounce of lye per quart (about 30 grams per liter). For full efficiency you need 20% lye by weight or 200 grams per liter of water.

The citric acid

1. Helps mitigate foaming,
2. Helps reduce the electrolyte caustic alkalinity and
3. Helps keep the electrodes clean longer. It is optional but recommended.

I recommend adding citric acid 1:1 with lye. So for one ounce lye use also one ounce citric acid.

No. It helps keep the plates clean longer (slightly increasing efficiency long term) and somewhat mitigates the caustic nature of the lye (only matters when you pour our the lye solution).

You will only add PURE WATER after the first fill (charge) of NaOH. The NaOH is a catalyst and is supposed to remain in the machine.

It occurs to me to ask… How much lye did you put in the machine? If 120 VAC version it should have been 1 oz (28 grams) per 3 cups (750 ml).

If you use too much lye, you will get foaming and lye will leave the machine.

No they complement each other.

The lye is the catalyst, lowering the electrical resistance of the distilled water so that the electrolysis can happen. You want as pure of lye as possible, to hopefully prevent impurities that cause foaming or make poisonous gasses or clog up the machine.

The citric acid helps keep the plates clean longer, mitigates the caustic of the lye and helps reduce foaming.

Or do I use just one (which makes more sense)?

Because it is not ‘mission critical’ for the function of electrolysis.

Do you suggest I use it?

Generally Yes. IF the Citric Acid is pure and doesn’t cause foaming.

The citric acid helps:

1. Mitigate the pH of the lye (safer to work with the solution)
2. Mitigate foaming (which causes lye loss)
3. Keep the plates clean longer (extending the machine’s functional life)

Some people have discovered that it is possible to use straight Citric Acid as a catalyst (instead of lye).

Citric Acid is a very POOR catalyst. It is very inefficient at allowing water to conduct electricity so takes about twice the voltage to push amperage across the cells (compared to efficient catalysts). This makes poor to no gas production and excess heat.

I recommend Citric Acid ONLY as an ASSIST to an efficient catalyst (like lye) because (as an acid) it tend to mitigate the caustic pH, it tends to mitigate foaming and it helps keep everything clean inside the electrolyzer.

BUT… It turns out that SOME brands of Citric Acid contain an oil that EXACERBATES foaming, so you can lose all your lye in a day (instead of years). So be sure your Citric Acid is high quality.

I’ve tested thousands of electrolytes and electrolyte densities and found Lye (aka NaOH, Sodium Hydroxide or Caustic Soda) to be the best all around choice. Balancing:

1. Efficiency (low voltage to push amperage)
2. Cost and availability (easily acquired at low cost)
3. Safety (of caustic)
4. Longevity (if no foaming, stays in the electrolyzer for years)
5. Clean (produces no poisionous gasses, like chloride or carbon dioxide)
6. Clean (produces no sediment)

So while you can add Citric Acid, it’s OPTIONAL and Lye at one ounce per quart (about 30 grams per liter) is quite adequate for health application of our electrolyzers (like the ER50 or the AquaCure).