​​How does H2Blue detect dissolved hydrogen gas?

H2Blue uses Methylene blue (MB), a compound commonly used in chemistry as an indicator and in medicine as a biological tissue dye, to detect dissolved H2 gas. As an oxidizing agent, MB is known to react with dissolved molecular hydrogen to produce the clear (reduced) form of MB, leucomethylene blue (leucoMB), as follows:


H2Blue contains methylene blue, a compound used as a biological tissue dye. Therefore, H2Blue can stain any surface it touches (possibly permanently, depending on porosity). It is recommended that skin, counter-tops, floors, clothing and other surrounding surfaces be protected from inadvertent splashing during use.  The user should wear safety glasses to protect eyes from splashing. Use of a mild abrasive cleanser will usually remove stains from most surfaces. Use soap & water to remove from skin.

​Package Description

The H2Blue bottle contains 10 mL of reagent, enough to perform approximately 50 tests (depending on your average H2 levels). Since the bottle capacity is approximately 13 mL, it will not appear to be completely full when received (bottles are filled using precision dispensing equipment). H2Blue comes in an LDPE plastic bottle with a child-resistant cap. The H2Blue bottle comes stored in a plastic graduated beaker with a screw cap. The beaker is used to measure the precise volume of hydrogen water (6 mL) required for accurate testing of dissolved H2 levels.  H2Blue ​should be stored in a cool, dry place, and should be used within 12 months of purchase.

 ​​Demonstrating the presence of dissolved H2:   

In addition to measuring dissolved H2 levels, H2Blue may also be used as a tool to simply demonstrate the presence of dissolved hydrogen gas. When used in this way, the user can collect a sample of the water to be tested (e.g an inch or two in a water glass, the amount is not critical), and then add a few drops of H2Blue. The drops will immediately turn clear, demonstrating the presence of dissolved hydrogen gas (H2). Likewise, the same can be done to a sample of any other water to show that it DOES NOT contain dissolved H2. For example, when H2Blue is added to so-called bottled "antioxidant" waters, the drops will not turn clear if the water does not contain dissolved hydrogen gas (plastic and glass bottles cannot hold dissolved hydrogen gas for very long).

H2Blue Video Tutorial

​​​​​​Using H2Blue to measure dissolved H2:

H2Blue is a reagent that reacts with water containing dissolved hydrogen gas, and turns "clear" when the dissolved H2 concentration is at least 0.1mg/L (ppm).H2Blue can be used to measure dissolved hydrogen levels by performing what chemists call a "titration". During titration, a substance of known concentration (theH2Blue reagent) is added to a precisely-measured volume of water (6mL) containing an unknown level of dissolved hydrogen gas (H2) . In the presence of dissolved hydrogen gas, the H2Blue molecules react with the dissolved H2 molecules, causing the blue molecules to turn "clear". As additional drops are added, the dissolved hydrogen molecules continue to be "consumed" until they are depleted. This is called the "titration endpoint". When the endpoint has been reached, additional drops will no longer turn clear, and the solution will remain blue. By counting the number of drops of H2Blue required to reach the titration endpoint , and then multiplying the number of drops by 0.1, the level of dissolved H2 gas in mg/L (ppm, parts per million) can be determined. For example, 8 drops x 0.1 = 0.8 mg/L of dissolved H2​ (see PPM Page for an explanation of parts per million).

pH Range

TheH2Blue reagent has been tested for performance accuracy in the pH range of 4 to 10. Although H2Blue will still detect dissolved H2  outside of this range, results may be skewed or reaction times may be slower.  

Quantity Pricing

Wholesale discount pricing in multiple tiers is available for customers wishing to purchase H2Blue in larger quantities. Please  Contact Us  for more information.

A note about using methylene blue as an indicator for dissolved H2 gas:

H2Blue contains a common dye, methylene blue, a compound used in biological applications. But, a solution of only methylene blue is not an effective dissolved H2 indicator. For a methylene blue solution to be used as an indicator for H2,  the addition of a catalyst is necessary. The catalyst is, by weight, the most expensive component in H2Blue.  

H2Blue Safety Data Sheet


As the equation indicates, after reacting with H2, MB, which is blue, becomes leucomethylene blue (LMB), and turns clear. The diagrams below show how the addition of H2 to MB changes the atomic structure of the MB molecule:

Usage & Storage

H2Blue is a laboratory-grade test reagent containing compounds not intended to be taken internally...keep out of reach of children, and store in a cool, dry location. Please downloadSafety Data Sheet for more information.

Insuring peak performance of H2 water devices:

When hydrogen water devices are new, they may produce good levels of dissolved hydrogen gas (H2). But, as calcium contained in the source water begins to accumulate on the electrodes and hoses, the dissolved hydrogen levels can begin to drop, sometimes in as little as a few weeks. By using H2Blue to measure dissolved H2 levels, you can be sure that your device is performing at peak levels. In addition to electric devices, H2Blue can also be used to insure the performance level of other H2 technologies, including hydrogen tablets, magnesium sticks, H2 reactor cartridges, and hydrogen-water filters.

​​​Helpful hints for measuring:

When measuring H2 water from water ionizers or hydrogen infusion machines, be sure to run the device for at least 20 seconds before taking the 6ml sample. This will insure that you are sampling fresh H2 water, not water which has been sitting in the machine.

The H2Blue spout is designed to dispense a precise droplet size for testing dissolved H2 levels.  When dispensing each drop, turn the bottle completely upside down, squeeze the bottle until one drop exits the spout, then release the pressure (which creates a small vacuum). Repeat this technique for each drop. Dispensing H2Blue in this way will help to prevent excess reagent from running down the spout.

After completing each measurement, be sure to completely rinse the graduated beaker to remove all H2Blue residue. If H2Blue residue is permitted to accumulate on the inside of the graduated beaker, this may result in inaccurate H2 readings.

Because dissolved hydrogen gas starts to escape immediately after the 6mL sample is taken, try to perform measurements as quickly as possible. Multiple drops of H2Blue can be added at once to save time, but do not add too many, which may cause you to pass the titration endpoint. Best results will be obtained when a measurement takes 1 minute or less.


Be sure to use only the beaker supplied with H2Blue, and use exactly 6mL of water by filling until the bottom of the water's meniscus is at the top of the 6mL graduation mark.

Fill the graduated beaker directly from the device without using any type of intermediate container (such as a drinking glass), and tilt the beaker slightly while filling to minimize any splashing, which could inadvertently force some of the dissolved gas out of the water.

* Because dissolved H2 gas is volatile, avoid shaking the beaker when adding drops, which can significantly reduce the dissolved H2. It is better to "swirl"the water or use a small straw (such as a coffee stirrer) to gently stir the reagent into the test sample.

When approaching the titration endpoint, be sure to count the last drop which causes the 6mL test sample to remain pale blue.


H2Blue is warranted to perform as described here for one year* from date of purchase. In the event that you are dissatisfied with the product, we will replace it or issue a refund at our discretion. Shipping charges are not covered by warranty and are not refundable. Please  Contact Us  for more information.

*12-month Pro-Rata

What if my H2 readings are lower than expected?

H2Blue will react with dissolved hydrogen gas and turn clear, provided that the dissolved H2 concentration is at least equal to the lower detection level of 0.1mg/L.  If your device is not producing detectable dissolved H2 levels, check for the following:

* Review tips for getting best results (see "Helpful hints for measuring" above)

* Limescale (from hard water) may have accumulated on the electrodes or plumbing;

1) Follow manufacturer's instructions for cleaning your machine, or send it to the factory for "deep cleaning"

2) If your machine has both upper and lower hoses, and the capability of reversing the polarity, you may be able to produce hydrogen water from the lower hose , using the opposite electrodes normally reserved for making the acid water. These electrodes may produce higher dissolved H2 levels as they are less likely to have any limescale accumulation.  Contact Us  for more information.​

* Source water mineral concentrations may be too low for adequate H2 production (alkaline ionizer) - add a mineral pre-filter cartridge to boost source-water conductivity

* The device may be malfunctioning and not producing any H2 gas- contact the manufacturer for troubleshooting procedures

* Because H2Blue is a "non-selective" oxidizer, the presence of high levels of other oxidizing or reducing agents, such as chlorine or oxygen (Brown's-Gas devices),  antioxidants (such as vitamin C), or some forms of glucose (sugars), may  interfere with H2Blue and give incorrect readings. Contact Us  for more information.

* Since H2Blue's resolution is 0.1mg/L per drop, failure for even one drop to turn clear does not necessarily indicate that there is no dissolved H2 in the water for a couple of reasons:
1) The water being tested could possibly have a concentration of only 0.1mg/L, which would cause only one drop to remain blue. This is because we always count the last drop in the titration which causes the reagent to remain blue (in this case, the first drop would also be the last drop). But, water with no dissolved H2 would also cause one drop to remain blue. Therefore, some ambiguity in the reading is possible when testing levels of dissolved H2 at or near the concentration of 0.1mg/L. Ideally, at least one drop should clear up to verify the presence of some H2, which would in fact represent an H2 concentration of 0.2mg/L.
2) A concentration of less than 0.1ppm could be present, e.g. 0.05mg/L, but be undetectable, since it is below the minimum detection threshold of the reagent.

* Finally, it is important to remember that H2 is not highly soluble in water. Therefore, even if your device produces large quantities of visible H2 gas, this does not mean that the level of dissolved H2 gas will be high. Next-generation hydrogen infusion machines include specialized devices called "dissolvers" specifically designed to boost the amount of dissolved H2 gas.


BecauseH2Blue contains ethanol, it must be packaged and labeled according to US DOT and international IATA regulations. Because the US Postal service will not accept products containing ethanol, we must use an alternative carrier. We use Fedex Ground to ship H2Blue within the US (lower 48) and Canada. Shipping to Alaska, Hawaii and all other international addresses is via Fedex Express (air)- please  Contact Us  about orders to international locations.