ORP testing by Walter Last

Ionized water has several health promoting qualities. I have no doubt that the most important of these is the strong antioxidant or reducing property of alkaline ionized water. This led me to experiment with my Jupiter Masterpiece (equivalent to the Technos Ionizer in North America) to establish the conditions for consistently generating the highest antioxidant potential in my water.

Here I want to share some of my experiences in the hope of helping others to improve the quality of their ionized water. I must confess that the task turned out to be much more difficult and frustrating than expected but I am very pleased with the final outcome.

Lets start with some basics. In chemistry oxidation and reduction are now commonly defined as gaining or losing electrons. Oxidation is the loss of an electron from a substance, while in reduction an electron is gained. Oxidation and reduction occur simultaneously in two substances. Oxygen is the most familiar electron acceptor or oxidiser. Iron rusts by combining with oxygen. Thereby the iron donates electrons and is oxidised while the oxygen gains electrons and is reduced.

The antioxidant activity can be measured as the Oxidation–Reduction Potential or O.R.P. For this I used an ORP meter (Milwaukee SM 500), which indicates the presence of free or loosely bound electrons as a negative ORP up to –1000 mV. An ORP of 0 is neutral while an oxidizing potential can be measured up to +1000 mV. The ORP scale officially extends from +1200 mV to – 1200 mV. However, with this method we cannot measure purely organic antioxidants, such as vitamin E as their electrons are much too tightly bound, although vitamin C is partly ionised and can be measured to some degree.

To confuse things, a high negative ORP can also result from a high level of dissolved hydrogen, and in this case it does not have any antioxidant property. Large amounts of hydrogen are produced at slow flow rates when the water becomes strongly alkaline with a pH over 10.0.

The principle of antioxidant activity is the availability of electrons to neutralize any so-called free radicals with oxidizing qualities that may damage biological systems. The electrons present in alkaline ionized water are highly reactive and react much faster than organic antioxidants to neutralize free radicals.

Furthermore, as we age our body structures lose elasticity; everything becomes more rigid. On a biochemical level this increasing rigidity is due to cross-linking of structural bio-chemicals, which in turn is due to a loss of electrons. Providing the body with an abundance of highly reactive electrons can be expected to slow cross-linking reactions and, with this, the aging process.

Finally, all biochemical energy in our body is produced by transferring electrons from food molecules onto inhaled oxygen. Having more available electrons may help us to produce more energy. This may be the reason why some individuals feel more energetic on ionized water.

From this outline you can see why I am so interested in a high negative ORP. The higher the ORP, the stronger the healing qualities. However, this does not mean that it is advisable for beginners to start with a high ORP. As with exposure to sunlight it is best to start with low doses and increase gradually, and even that may from time to time produce some healing reactions as with temporary inflammations, mucus discharge and skin rashes.

Additional healing factors for most individuals are the alkalinity of the water and its low surface tension. Most of us are overacid and benefit from our lymph fluid becoming more neutral. However, this is only a minor factor in using ionized water as we can alkalize more quickly and cheaply by taking sodium bicarbonate. The lower surface tension, on the other hand, improves the absorption and use of nutrients.

In my initial experiments it appeared that the slower the flow rate the higher the negative ORP. Therefore I tried to let the water run at the slowest possible rate, about 7 minutes per litre and at the highest ionising setting of 5. This usually gave an ORP of up to –350 mV and a pH of about 10.7. A flow rate of 5 minutes per liter tended to give somewhat lower ORPs and a pH of about 10.0 to 10.5. However, a slow flow rate combined with a high pH eventually caused problems with calcium precipitation. My bore water out of the tap has an ORP of about +250 and a pH of 7.1.

Then I obtained a TDS meter, which measures total dissolved solids or ionic minerals in parts per million or ppm. I found that my bore water has about 350 ppm. After some good rain it would drop towards 300 ppm and also the ORPs were usually lower, say about -250 mV and sometimes much less, even without any rain.

A friend used town water supplied from river water, which in turn was rainwater with a low TDS of about 150 ppm. Initially his ORP readings were only –60 to –120 mV. The highest ORP was with a very slow flow rate that produced a pH of 11.7. I suggested using a calcium insert to increase the mineral content of the water and that increased the ORP to about –200 at a higher flow rate and lower pH.

After ionizing the TDS value of the reduced water may be higher or lower than the original water. At lower pH values up to about 9 or 9.5 the TDS tends to increase, either because minerals are now more concentrated or just more strongly interacting with the electrodes of the TDS meter. However, with higher pH values the TDS becomes increasingly lower and continues to drop over time as large amounts of calcium precipitate.

Coming back to my experiments, I was surprised to notice that higher flow rates could often generate higher ORPs with lower pH. With a flow rate of between 1 and 4 minutes per litre I could sometimes obtain ORPs of over -600 mV at a pH of 8.5 to 9.5. Once I even had an OPR of over -600 with a fast flow rate and a pH of 7.9. However, after some time the ORPs dropped back to about –300 mV. (I know now that this was due to calcification of the alkaline electrodes).

Sometimes I had the highest ORP at a flow rate of nearly 1 minute per liter and sometimes at 4 minutes per liter but usually somewhere in-between and close to 3 minutes per liter. However, this may be different with different ionizers and different water. Ionizers with more or stronger electrodes obviously will have higher optimal flow rates, while water with lower mineral content will probably need lower flow rates.

The following table shows ‘typical’ differences in ORPs at different flow rates in seconds per liter. These were measured simultaneously with three different probes to show their varying sensitivities. The first line for each flow rate shows the results about 30 to 60 minutes after ionising and the second line in the same samples the next day.

Most values are higher the next day. To see how long properly stored water keeps its charge I kept a sample for 10 days. I thought by waiting for 10 days I could more easily calculate the daily rate of decline. To my surprise it measured over –700 mV.

This inspired me to measure ORP values on consecutive days in the same batch of ionised water, which I stored separately in several small bottles. The results are in the following table:

TIME	PROBE 2	PROBE 3	PROBE 4
30 minutes	-189	-260	-296
2 days	-495	-555	-683
4 days	-522	-675	-747
5 days	-674	-704	-746
6 days	-663	-736	-743
7 days	-707	-732	-736

This means that to obtain reliable measurements one should repeat the measurements for several days. Depending on the sensitivity of the electrodes the highest value may be reached somewhere between 3 and 7days. Most surprising to me was the close agreement of all 3 probes on the seventh day. Sometimes a reading can be high to start with but then it is not very stable and may for several days show strong fluctuations. (However, see also below my more recent results with the Modified Vinegar Cleanse).

I assume that the reason for this unexpected behavior of the probes is the presence of oxygen and other oxidizing species in the reduced water. These gradually become extinct by reacting with the reducing chemicals. Electrodes can then give a truer picture of the number of reactive electrons in the water. While the amount of oxidising ions can be expected to be very small as compared to the reducing ions, they have a strong influence on the probes because of the exponential nature of the electrode sensitivity.

To illustrate tis point, a certain number of reducing or oxidizing ions may give an ORP reading of + or –100. A ten times greater amount may read + or –200 and a hundred times greater number + or – 300. In this example only 1% of oxidizing ions will reduce the ORP reading from –300 to –200. After several days almost all of the oxidizing species will have been eliminated and the ORP measurement is now close to –300.

However, in reality the exponential effect is even greater. Vinny Pinto on his Negative Hydrogen site (www.negative-hydrogen-ion.org) has calculated that every increase in negative ORP by 59 mV means a tenfold increase in the number of reactive electrons, while a 118 mV change in the ORP relates to a hundredfold change in electrons. Extending these calculations somewhat further we obtain a ten thousandfold and a millionfold change in electron density when the ORP changes by 236 mV or 354 mV.

To see how the ORP changes in less strongly reduced water during storage I made two additional tests. I produced one sample with a flow rate of 2 liters per minute on the highest ionizing setting of 5 and another one at the same flow rate at the lowest ionizing setting of 1. The results were as follows:

TIME	PROBE 2	PROBE 3	PROBE 4
1 hour	-151	-241	-274
1 day	-138	-280	-298
2 days	-141	-286	-285
3 days	-090	-179	-171

TIME	PROBE 2	PROBE 3	PROBE 4
1 hour	-031	-099	-115
1 day	-004	-094	-110
2 days	+042	+050	+085

If you compare table 3 with table 2 you will notice that the first measurements from 30 to 60 minutes after ionizing are very similar. However, the maximum values obtained after several days of storage show that the water in table 2 had about 50 million times more available electrons than the water in table 3, which was produced at a six times faster flow rate.

Even more striking is the comparison with table 4. Here the number of electrons is so low that the water cannot hold its charge for long. The reason why the measurements of low-ORP water do not increase much during storage is the small amount of infiltration of oxidizing species with fast flows. Therefore in this case the initial measurements are a good indication of the true value, unlike with slower flows that allow much greater mixing of ions.

Other factors that may influence the ORP are the rate of flow between acid and alkaline water outlets, the time since the electrodes were last cleaned with vinegar and whether the water is collected at the beginning or near the end of an ionising cycle. Generally readings may be somewhat higher soon after vinegar cleaning and near the end of a cycle but this is not consistent.

In order to slow down the flow-rate of the alkaline water I use a very thin 4 mm alkaline outlet hose as used for oxygen masks. This then greatly increases the flow-rate of the acid water. Once I used a wide 8 mm alkaline outlet hose, the same as for the acid outlet, and the flow of the acid water became very slow. However, it had a very strong ozone-like smell.

While most vitamins suffer losses during cooking, the rate of degradation is much higher in alkaline than in neutral conditions and even less with an acid pH. Therefore, habitually cooking with alkaline water can lead to vitamin deficiencies. This was noticed especially in some regions of

England

where baking soda was added to the cooking water in order to preserve the colours of vegetables. Furthermore, we need strongly acid gastric juices for proper digestion and absorption of proteins and some of the minerals and vitamins.

Individuals with weak stomach acid commonly suffer from mineral deficiencies and often have soft fingernails and poor hair quality in addition to lack of energy and other problems. Also vitamin B1 requires gastric acid for its absorption. Commonly we produce less stomach acid as we get older but even many young individuals, such as asthmatics, do not produce enough stomach acid.

Drinking alkaline water on its own does not cause a problem because the stomach does not deliberately produce more acid to neutralize it. Also the mineral density of ionized water is not very high and it is easily neutralized. A glass of water (200 ml) at a pH of 10.0 changed to pH 6.9 with the addition of 16 drops of lemon juice.

Alkaline water with a lower mineral content would require even less acid to neutralize. An observed drop in ORP with the addition of organic matter is not necessarily a disadvantage. I assume that the reacting electrons just are more tightly bound but will still be available to us after absorption.

It is different if a large amount of strongly alkaline water is combined with food, either by cooking in it or when drinking close to a meal. Then the stomach is required to produce acid to digest the food but instead the acid is partly neutralized by the alkaline water. This is not much of a problem at lower pH levels, perhaps up to a pH of 8.5 or for individuals with strong gastric acid but it may be a disadvantage for others. A safe interval between drinking strongly alkaline water and a meal is about 30 minutes before and 2 to 3 hours after the meal.

The next question involves storing ionized water to preserve its negative charge. Some of the influences on its stability are as follows. A small amount of water exposed to air loses its charge much faster than a larger volume. I measured, for instance, a charge of -328 in half a glass of water go to +6 within 7 hours. In about one litre of water from the same batch the charge was still -20 after ten hours.

Another influence is the temperature. When I heated a cup of water to boiling temperature for a few minutes it had lost all of its negative charge after cooling, while the unheated water was still about -300. However, it is not the temperature as such that causes the fast discharge, but rather the strongly speeded-up reaction of the negative charge with the oxygen in the air. In a laboratory experiment it was found that autoclaved water only lost its charge if it was exposed to air, without any air in the sample it did not discharge.

Initially I believed that refrigerating or even freezing the ionized water was required to preserve its charge for days or weeks until I found that exposure to light discharged the water. Now I store the water in brown glass bottles (200 to 750 ml) filled to the top but not touching the top, and in addition I keep them in a closed cupboard. The bottle top needs an airtight seal otherwise the water will discharge much more quickly. However, the charge in an only partly filled bottle keeps longer under refrigeration and very much longer in a frozen sample.

As mentioned before, the negative charge of water produced with a slow flow rate may still rise during storage. However, this does not mean that it is more desirable to drink stored water rather than immediately after producing it. Antioxidant properties do not increase during storage, only active oxygen species are being eliminated and it may actually be beneficial to ingest some of these.

I also found that the steel outlet pipe of the ionizer unit reduces the negative charge and even slightly lowers the pH. The degree of deterioration depends on the strength of the water flow. With a strong flow (1 minute per litre) the reduction in the charge by the steel pipe was negligible as compared to a plastic hose.

However, when I inserted a thin plastic hose into the steel pipe and collected water simultaneously from both outlets at a very low flow rate, there was a great difference. The water coming out of the plastic hose had -278, while the ORP of the water running through the steel pipe was only -170. This shows that we should not store charged water in contact with blank metal as for instance with an unprotected metal bottle top.

Scientific articles tend to call ionized water ‘Electrolyzed Reduced Water’ or ERW for short. The chemical reactions during water ionization are not well understood. I believe the main reactions to be as follows.

The negative electrode or cathode donates electrons while the positive electrode or anode accepts electrons out of the solution. In the water flowing past the electrodes positive minerals or cations, such as sodium and calcium, move towards the cathode while negative anions, such as chloride and fluoride, migrate towards the anode. Electrons emitted by the cathode are attracted by the positive charges of cations and react with them to form neutral metal atoms such as sodium or calcium.

These metal atoms are rather unstable and highly reactive. They immediately react with water molecules to form hydroxides, such as sodium hydroxide, while the surplus electron is transferred to the hydrogen ion to produce a neutral hydrogen atom. Hydrogen atoms, in turn, are also very unstable and react either with other hydrogen atoms to form hydrogen molecules, or they may accept a second electron from the cathode to complete their electron shell and become negative hydrogen ions.

Expressed in simple chemical equations, using table salt as an example, this looks as follows:

Sodium ion becomes a neutral atom by accepting electron from cathode: Na⁺ + e^- Þ Na

Sodium atom immediately reacts with water to form sodium hydroxide by donating an electron to the hydrogen ion, which in turn becomes a hydrogen atom:

Hydrogen atom either combines with another hydrogen atom to form a hydrogen molecule or it accepts a second electron to form a negative hydrogen ion:

Sodium hydroxide and other common hydroxides are highly soluble except for calcium hydroxide, which starts precipitating out of calcium-rich water when the pH goes above 10. Drinking water containing hydroxide is not a problem, at least up to a pH of 10 or 11, because normally so little is present that a few drops of lemon juice or gastric acid will neutralize it.

Negative hydrogen ions are the basis for the negative potential and antioxidant properties of reduced water. They can become reasonably stable by attracting the positive hydrogen potentials of water molecules. A water molecule is a weak dipole with a negative potential at its oxygen and positive potentials at each of its hydrogen atoms. The negative hydrogen ion is now in a protective cage surrounded by probably six water molecules. I assume that in this form it can pass the intestinal wall and reach the bloodstream.

Theoretically negative hydrogen ions may also react with cations to form unstable hydrides, such as sodium hydride. These, too, may be temporarily stabilised in protective water molecule cages. Other possibilities are the formation of negatively charged hydrated cation complexes and colloids. All of these are very unstable and likely to react with any similar unstable oxidizing species present. This may account for the initial strong fluctuations in the ORP potential. Contrary to theoretical expectations, measurements have shown that reduced water is higher in dissolved oxygen than the tap water before ionizing.

This model shows how important it is for sufficient minerals to be present. Fewer minerals require a slower flow rate for this process to work. However, at a slower flow rate more water molecules are being split and more hydroxyl ions as well as hydrogen atoms are being formed. This causes the reduced water to become more alkaline but does not lead to more negative hydrogen being formed. The abundance of hydrogen atoms now leads mainly to the formation of hydrogen molecules, which escape as gas bubbles.

A similar process near the anode leads to the formation of neutral hydroxyl molecules. These react with each other to form water and highly reactive oxygen atoms, which then combine to form stable oxygen molecules in addition to ozone, hydrogen peroxide and possibly other oxygen species such as hypochlorite.. It is likely that in addition also some chlorine is being formed.

Previously negative hydrogen was thought to be present only in highly heated gases but more recently it has been found that it is widespread in biological systems, including fresh (organic) fruit and vegetables. It is also relatively high in mountain streams and rainwater, especially during thunderstorms. Negative hydrogen is now thought to be the primary antioxidant of all biological systems. For an interesting site on negative hydrogen and ionised water see www.negative-hydrogen-ion.org.

Strongly oxidized water is used by an increasing number of hospitals in the

USA

as the preferred disinfectant because it is apparently cheaper, safer and more effective than conventional disinfectants in eliminating pathogenic microbes. Commonly batch ionizers are used for this purpose and the water is rather high in salt (sodium chloride).

The acid water from a through-flow ionizer is usually not strong enough as a household disinfectant but may be used on parts of the body that are infected with fungi or other microbes, we may also use it for oral hygiene.

Normally, as a user of reduced water, you do not need to be too concerned with achieving the absolute maximum antioxidant potential from your ioniser. I did this mainly to find some general rules for consistently producing high-quality reduced water. Nevertheless, you should know the approximate mineral content of your water and preferably have the ORP checked sometime after set-up and whenever there is a change in operating conditions.

There are different possibilities for doing this. Ideally you may have a local distributor of water ionizers who has the necessary instruments and can help you setting your ionizer up for optimal efficiency. Alternatively, you may find other ionizer owners in your area and share the cost of buying an ORP meter, a TDS meter and an electronic pH meter. You may also contact a local water treatment or testing company.

If you use municipal town water that comes mainly from river and rainwater, you can expect to have low mineral values and should consider installing a small tank to supply your ionizer with water. You may just use a 5 to 10 liter container about 1.8 to 2 m higher than the inlet of your ionizer. The container does not need to have a bottom outlet as you can siphon the water over the top. Use wide hose connections (8 mm) without any restricting taps otherwise you may need more height for a sufficiently strong water flow. You can regulate the flow with an external hose clamp.

If you do not know the mineral content of your water but suspect it to be low, you may just add 2 g or half a teaspoon of salt or better twice this amount of hydrated magnesium chloride per 10 liters of water. Otherwise add enough to get a TDS value of about 350 to 400 ppm in your water. By adding more minerals than that I did not get any higher ORPs in my tests, although that may be possible with stronger electrodes or higher flow rates.

Pure rainwater in plastic or metal tanks is very low in minerals with about 20 to 50 ppm and not suited for ionising. However, it is easy to add sufficient minerals to raise the TDS to over 300 ppm. The cheapest way of doing this is by adding salt at a rate of about 3 g per 10 liters. Assuming that the TDS was 50 ppm before, this will raise it to about 350 ppm. If you prefer to add magnesium chloride instead, you may buy a 25 kg bag of hydrated magnesium chloride (from a chemical company) and add about 4 g per 10 liters in addition to 2 g of sodium bicarbonate for a truly ‘unique water’.

If you do not have an ORP meter it is advisable to check the pH of the alkaline water or make an ORP colour test once a week. Otherwise you may just produce filtered but not ionised water without realising what is going on. This happened to me when I had not ORP-tested my water for about 2 weeks. To my surprise the ionized water had the same ORP and pH as the tap water despite all the indicator lights working, the flows between acid and alkaline water remaining normal and having done a vinegar cleanse only a week before.

As I use bore water high in calcium, I suspected that the cathode (the electrode that produces the alkaline water) was completely coated with calcium carbonate and that the normal vinegar cleanse was not sufficient under these conditions. This turned out to be correct.

If your water is high in calcium I now recommend the following procedure. Remove the alkaline outlet hose, tilt the ioniser backwards and use a large syringe to slowly inject about 20 to 40 ml of white vinegar directly into the alkaline outlet. If you have difficulty buying a large syringe from a chemist, you may also pour the vinegar through a small funnel or use a suitable spray bottle.

If you put your ear close to the alkaline outlet you can easily hear the bubbling inside. After about 10 minutes the bubbling stops and now you inject 10 to 20 ml of additional vinegar. After 5 to 10 minutes the bubbling stops again and you inject more vinegar. In this way you continue until there is no further or only very little bubbling with additional vinegar. Then do a 2-minute cleaning cycle before using the ioniser setting.

If it is badly calcified you may have to inject vinegar more than 20-times. Preferably do this regularly every 2 weeks to avoid a massive calcium build-up. Occasionally you may also perform a normal vinegar cleanse by pouring vinegar into the opened filter. As an alternative method, I have now started injecting 10 to 20 ml of vinegar just once every other day after producing my ionized water.

Since starting the new method of vinegar cleanse, my alkaline water consistently measures more than –600 mV and usually more than –700 mV immediately after producing it and the ORP is very stable.

I use a Milwaukee ORP meter, the SM 500 with an official working range of +999 to –999 mV, although it indicates up to + or – 1999 mV. Like other ORP meters it has a probe with a platinum electrode that is sensitive to the flow of electrons and a calomel electrode as a stable reference electrode.

Initially ORP testing was very frustrating as the measurements were rather erratic, partly due to the inherent instability of the ionized water but mainly because of the instability of the probes. However, eventually I learned to keep the probes sensitive and accurate. However, when measuring simultaneously with several probes results still continue to vary widely with weakly ionized water that is with readings below about –200 mV. All of the described difficulties apply only to measuring the ORP of alkaline ionized water. In conventional reducing liquids such as vitamin C solutions there is no problem with ORP probes.

Most of the eight probes that I worked with were rather slow and results consistently too low right from the time of purchase compared to a good probe used simultaneously. However, more recently I found several ways to improve electrode performance. For instance after first testing a new probe with the ORP Standard solution, ionized water then gave a reading of –136. Two other probes showed –556 and –548 mV in the same sample. After I gently cleaned the platinum wire for a few seconds with fine sandpaper it immediately read –552 mV.

However many probes are not stable and need frequent sandpapering to keep them sensitive and accurate. You can notice this by measurements starting rather low and creeping up only slowly. To give an example, a probe may start measuring at –200 and take 10 to 30 minutes to reach a highest value of -500 mV. After sensitizing the probe and measuring the same sample of ionized water it may start at –450 and in 1 to 5 minutes reach a stable endpoint of –700 mV.

Another and often better way to keep your probe sensitive is by frequently immersing it for 5 to 10 minutes in strongly oxidized acid water of +800 to +1100 mV. If the water is weaker, you may keep the probe in it for longer. One probe that I presently work with sometimes gets its best performance only after using sandpapering as well as immersion in oxidized water before measuring.

It also helps to immerse a probe for an hour in 3 or 6% hydrogen peroxide or clean the electrode tip with a cotton swab soaked in 35% hydrogen peroxide. While this tends to improve electrode performance, it is much less effective than immersion in acid water with a high positive ORP.

With batch ionizers it is generally easy to obtain acid water with a high positive ORP. With through-flow ionizers you may need to restrict the volume of the acid outflow with a clamp or by similar means and use the highest setting as well as water with a high mineral content. The high positive ORP is very stable and keeps for weeks or months in a closed bottle, which does not need to be filled to the top.

Instead of keeping probes immersed in ORP storage solution I prefer to store my probes moist in the supplied airtight plastic cap but not immersed in any liquid. Another occasional problem with probes is a black fungus growth in warm weather. You may brush this gently off with a toothbrush or with a cotton swab dipped in hydrogen peroxide.

Some probes need very little attention while others need a lot. Frequently alternating measurements between reducing and oxidizing water seems to be good for all of them and it also keeps any fungi away. After experimenting for a while you will get a feel for the needs of your probe.

Colour tests with pH paper or a liquid pH indicator are relatively cheap and usually sufficient when working with an ioniser. You may also make a simple colour test for the reducing power of your ionised water. In addition to using this test instead of an ORP meter, you may also use it with unusual results to check whether your OPP meter is still working properly. Buy some Condy’s crystals or potassium permanganate from a chemist or gardening shop.

Dissolve a tiny amount of the crystals in some water to make a deeply colored purple solution. Fill one of two identical clear glass jars or bottles with water before ionizing and the other with ionised water. With a dropper add sufficient drops of the purple solution to the non-ionised water until it appears slightly pink. Then add the same number of drops to the ionized water. Place both on a white surface and look down from the top.

The reducing potential is indicated by the time it takes for the ionized water to lose its pink colour. With a very high negative ORP of about –700 mV you notice the color fading within a few minutes and after 10 minutes the water may be nearly clear. In contrast, with a low ORP of –100 to –200 mV you may get the first hint of a color difference between both samples after about 30 to 60 minutes and it may take 2 to 3 hours until the ionized sample is more or less clear. You may estimate intermediate ORP values from the times of the first definite color change and the complete discoloration of the sample. During this test protect the ionized sample from strong light and minimize exposure to air.

These observations with through-flow ionizers generally also apply to batch ionizers. Lower mineral concentrations require longer ionizing times and produce greater pH and lower ORP changes. It is advisable to use water low in calcium, otherwise the cathode soon becomes coated with calcium deposits during long ionizing periods and loses its effectiveness or frequently needs to be cleaned. Furthermore, it is advisable to protect the ionizer from light during long ionizing periods.

To learn more about the conditions for creating a high negative ORP I acquired a cheap batch ionizer with a volume of about 4 litres. The membrane consists of a 10 mm porous ceramic plate with the two titanium electrodes (130 x 70 mm) touching the ceramic membrane on each side. The power source is 9 V.

My first test with bore water reached –219 mV after 10 hours and –238 after 20 hours. The ORP diminished during storage on subsequent days. The manufacturers recommendation is to add just 1 drop of lemon juice to distilled or de-ionized water. This produced a maximum ORP of –193 after 20 hours and returned to a positive ORP by the next day. The alkaline water reached a pH of 9.6; by adding 5 drops of lemon juice to a glassful the pH dropped to 7.0.

With a 12 V power pack I reached higher values and even more so with 20 V. With this I used rainwater with added magnesium chloride. A higher ppm resulted in higher ORPs, generally between –300 and –350 after 3 hours. Values continued to rise during storage to over –700 after 6 to 9 days.

However, 20 V was too much for the anode, which corroded quite noticeably. With voltages over 12 V protected anodes are required; either plated with platinum or mixed metal oxides. Alternatively, if the water is very low in chloride ions then no chlorine will be formed and no corrosion is likely to occur.

However, the greatest improvement came when I bent the electrodes so that instead of touching the ceramic membrane, there were now several millimetres of space between membrane and electrodes. With 12 V and even 9 V I now obtained ORP values of –400 and higher after 3 hours and over –500 and –600 after 10 hours. Values continued to rise during storage to about –750 mV after 6 days. For these latest tests I used rainwater with magnesium chloride added to approximately 300 ppm.

Another and bigger batch ionizer with 10 litres volume has an anode that is protected with mixed metal oxides. With this I can use 24 V without causing corrosion. The plates are about 30 mm apart. Using rainwater with the addition of magnesium chloride and a small amount of sodium bicarbonate to 300 - 400 ppm I get over –700 mV in one hour and about –800 mV in 2 hours. Generally I add a level teaspoon of hydrated magnesium chloride and half a level teaspoon of sodium bicarbonate to 10 litres of rainwater. You may also use potassium bicarbonate instead of sodium bicarbonate.

Because of the composition of magnesium chloride with one cation and two anions, it produces acid oxidized water with an ORP of more than +1000, which can be used as a very powerful household or commercial disinfectant, however, be aware that it contains chlorine. Acid water with a lower ORP and free of chlorine can be produced by using minerals that do not contain chloride.

Generally, with batch ionizers short ionising times are desirable. Factors that shorten ionizing times are:

With my Masterpiece ionizer I generally prefer to use an ionizer setting of 5 (maximum), a flow rate of 3 minutes per liter and a mineral content of about 350 to 400 ppm. With this I now routinely obtain maximum ORP values of about –700 mV with which I am quite happy. When I use the batch ionizer I get –700 to –800 mV in 1 to 2 hours.