Hello, dear aquarists!

homemade Ph-test

What is Ph? This is an indicator of the acidity of water. In everyday life, rarely does anyone test water for acidity. But every self-respecting aquarist is simply obliged to check the water in the tap, since this is what he will use as the environment for his fish. How can I do that?

At the moment, specialized stores sell special Ph tests. What are they? Well, these are strips of paper that, upon contact with water, turn into a certain range of colors. And each color spectrum corresponds to its own acidity index (Ph).

It seems that everything is in order, the issue is resolved and you can go buy these same tests. But there is one caveat: the price! The cost of these PH tests is quite high. And why spend a lot of money if you can make a similar test indicator in , spending mere pennies? Well, okay, not kopecks, but rubles, but within reasonable limits. How much exactly? And exactly as much as it costs...a head of red cabbage! Surprised? Of course: I myself was surprised at how smart we Slavs are! But enough compliments: let's move on to making the dough. So!

As I just said, you need to buy a small (0.5-1kg) head of red cabbage. I repeat: RED cabbage, no other cabbage is suitable for this purpose!

We bring cabbage home. Now take a knife and chop the cabbage. Place the shredded cabbage in a saucepan and fill with water. put on medium heat. As soon as the water boils, turn the heat to low and cook the cabbage for half an hour. After thirty minutes, turn off the heat and let the pan cool to room temperature. Has it cooled down? Fine. Now you need to filter the resulting cabbage broth several times to get rid of sediment. To do this, take some container, cover it with gauze and strain the cabbage broth through the gauze. You can eat all that is left of the cabbage (why, boiled cabbage is quite tasty).

Now we take printer paper and cut it into long strips. Cut a hundred pieces: it will last for a long time! Dip these strips into cabbage broth and leave them there for two to three hours. After a while, carefully remove them from the broth and lay them out on some surface (on a tray, for example) to dry. When dry, your Ph-test (test strips) will turn grayish or blue-gray in color. (By the way, the broth from red cabbage will have a completely black color).

Once the strips are dry, you can begin testing them. Of course. that you do not have a measuring (comparative) spectral scale with acid level indicators. But this is not a problem, since it is easy to make it yourself. Take a ruler and a piece of thick white cardboard. From this cardboard you must cut a strip 15 centimeters long. Then, mark the measurements on the strip (every centimeter) from 1 to 15 (in short, make a drawn ruler, what’s not clear?).

Take colored pencils (or markers). And now - attention: shade in red the distance from 1 to 4 cm; next, take a crimson color and shade a distance from 4 to 8 centimeters; further - purple, from 8 to 9; then blue, from 10 to 11; then green, from 12 to 13; and finally yellow, from 13 to 15. Now you have a spectral scale. Each color spectrum corresponds to a level of acidity (Ph). It roughly looks like this: from 1 to 6 - acidic water; from 6 to 8 - neutral; from 9 to 12-13 - optimal (basic, fundamental). As a rule, the indicator does not show the yellow spectrum.

To strengthen your confidence in working condition homemade Ph test, I suggest testing the strips on vinegar (the strip should turn red spectral color, which corresponds to number 2 on your spectral scale), soda (the strip should turn purple, well, or very close to purple - after all, our Ph tests are homemade. Therefore , there is no need to wait for 100% compliance.In this case, the indicator (color shade) of the spectrum of soda will be 5-8), milk (color - raspberry or manganese). In this case, the digital value should be about 6-7 (milk has a Ph value of 6.8).

I hope this article will help you in your water acidity testing decision.

All the best to you and see you again!

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Instructions indicator paper - instructions litmus paper measure pH

Litmus paper Instructions for use

Indicator paper Instructions for use

By determining the pH of your saliva every day, you can monitor the condition of your body.

For identification of acids and bases.

For normal human metabolism, it is necessary that the acid-base balance be maintained within certain limits.

Solutions and liquids with respect to their acidity are considered:

neutral at pH = 7

acidic at pH< 7

alkaline at pH > 7

Acidity of urine

If the urine pH level fluctuates between 6.0 - 6.4 in the mornings and 6.4 - 7.0 in the evenings, then the body is functioning normally. The most optimal level is slightly sour, in the range of 6.4 - 6.5. A urine pH value below 5.0 indicates its sharp acidification, above 7.5 indicates its sharply alkaline reaction.

The reaction of urine determines the possibility of stone formation: rats - in an acidic environment, oxalate - in a neutral-acidic environment, phosphate - in a more alkaline environment. For example, uric acid stones virtually never occur when the urine pH is greater than 5.5, and phosphate stones never form unless the urine is alkaline. The best time to determine the pH level is 1 hour before or 2 hours after a meal.

Check the pH level twice a week 2-3 times a day.

Using indicator litmus paper pH test, you can easily, quickly and accurately monitor the response of urine to changes in the type of diet, the use of medications or dietary supplements. Positive pH dynamics can serve as a criterion for the correctness of the chosen diet or treatment.

The acidity of urine varies greatly depending on the food taken, for example, eating plant foods increases the alkaline reaction of urine. The acidity of urine increases if meat foods rich in proteins predominate in a person’s diet.

Heavy physical work increases the acidity of urine.

Increased acidity of urine is observed with increased acidity of the stomach. Reduced acidity of gastric juice does not affect the acidity of urine.

The acidity of urine changes in many diseases or conditions of the body, so determining its acidity is an important diagnostic factor.

Saliva acidity:

The acidity of saliva depends on the rate of salivation. Typically, the acidity of mixed human saliva is 6.8-7.4 pH, but with high salivation rates it reaches 7.8 pH. The acidity of the saliva of the parotid glands is 5.81 pH, of the submandibular glands - 6.39 pH. In children, the average acidity of mixed saliva is 7.32 pH.

Optimal measurement from 10 to 12 hours. It is better to measure it on an empty stomach, two hours before or two hours after a meal. Salivation decreases in the evening and at night.

To increase salivation, in order to increase the pH of saliva, it is good if there is a piece of lemon on the plate; it even with visual perception increases salivation. Food should look appetizing, served on beautiful dishes, appetizingly decorated with herbs and/or vegetables, it should, as they say, please the eye! Not only the saliva flows, but also the juices in the body, preparing for the process of digesting food. This is the mental phase of digestive secretion.

Acid gastroesophageal and pharyngolaryngeal refluxes reaching the oral cavity play a leading role in the occurrence of oral pathology. As a result of the ingress of hydrochloric acid, the acidity of mixed saliva decreases below 7.0 pH. Saliva, which normally has alkaline properties, at low pH, especially at values of 6.2-6.0, leads to focal demineralization of tooth enamel with the appearance of erosions of hard dental tissues and the formation of cavities in them - caries. The amount of mucus on the mucous membrane increases, the gums become swollen and inflamed.

When the acidity in the oral cavity decreases, the acidity of dental plaque decreases, which causes the development of caries.

Bacteria in the mouth thrive in the absence of air. Saliva, rich in oxygen, actively prevents their reproduction. Bad breath occurs when the flow of saliva slows down, for example during sleep. Excitement, hunger, pronouncing a long monologue, breathing through the mouth (for example, with a runny nose), stress - dry out the oral cavity, leading to a decrease in the pH of saliva. A decrease in saliva flow inevitably occurs with age.

You can use a slightly alkaline mouth rinse with water with the addition of soda and also take it orally between meals, proposed by Professor A.T. Ogulov. - slightly alkaline pH 7.4-8. Rinsing the mouth with soda water occurs for various inflammatory diseases of the gums and teeth and for general acidification of the body.

You can set the desired pH of water for rinsing or ingestion using litmus indicator paper. There cannot be recipes with the required proportions, because... Each region has its own water, with its own pH. Therefore, it is necessary to have indicator paper on hand.

Vaginal acidity

The normal acidity of a woman's vagina ranges from 3.8 to 4.4 pH and averages 4.0-4.2 pH.

Vaginal acidity in various diseases:

* cytolytic vaginosis: acidity less than 4.0 pH

* normal microflora: acidity from 4.0 to 4.5 pH

* candidal vaginitis: acidity from 4.0 to 4.5 pH

* Trichomonas colpitis: acidity from 5.0 to 6.0 pH

* bacterial vaginosis: acidity greater than 4.5 pH

* atrophic vaginitis: acidity greater than 6.0 pH

* aerobic vaginitis: acidity greater than 6.5 pH

Lactobacilli (lactobacillus) and, to a lesser extent, other representatives of normal microflora are responsible for maintaining an acidic environment and suppressing the growth of opportunistic microorganisms in the vagina. In the treatment of many gynecological diseases, restoration of the lactobacilli population and normal acidity comes to the fore.

Sperm acidity

The normal acidity level of sperm is between 7.2 and 8.0 pH. Deviations from these values are not in themselves considered pathology. At the same time, in combination with other deviations, it may indicate the presence of a disease.

An increase in the pH level of sperm occurs during an infectious process. A sharply alkaline reaction of sperm (acidity approximately 9.0-10.0 pH) indicates prostate pathology.

When the excretory ducts of both seminal vesicles are blocked, an acidic reaction of the sperm is observed (acidity 6.0-6.8 pH).

The fertilizing ability of such sperm is reduced. In an acidic environment, sperm lose motility and die. If the acidity of the seminal fluid becomes less than 6.0 pH, the sperm completely lose their motility and die.

Acidity of tears Normally - from 7.3 to 7.5 pH.

Acidity in the stomach. High and low acidity

The minimum theoretically possible acidity in the stomach is 0.86 pH.

The maximum theoretically possible acidity in the stomach is 8.3 pH.

Normal acidity in the lumen of the body of the stomach on an empty stomach is 1.5-2.0 pH.

The acidity on the surface of the epithelial layer facing the lumen of the stomach is 1.5-2.0 pH.

The acidity in the depths of the epithelial layer of the stomach is about 7.0 pH. Normal acidity in the antrum of the stomach is 1.3-7.4 pH.

The cause of many diseases of the digestive tract is an imbalance in the processes of acid production and acid neutralization. Long-term hypersecretion of hydrochloric acid or lack of acid neutralization, and, as a consequence, increased acidity in the stomach and/or duodenum, causes so-called acid-dependent diseases. Currently, these include: peptic ulcer of the stomach and duodenum, gastroesophageal reflux disease (GERD), erosive and ulcerative lesions of the stomach and duodenum while taking aspirin or non-steroidal anti-inflammatory drugs (NSAIDs), Zollinger-Ellison syndrome, gastritis and gastroduodenitis with high acidity and others.

Low acidity is observed with anacid or hypoacid gastritis or gastroduodenitis, as well as with stomach cancer. Gastritis (gastroduodenitis) is called anacid or gastritis (gastroduodenitis) with low acidity if the acidity in the body of the stomach is approximately 5 or more pH units. The cause of low acidity is often atrophy of parietal cells in the mucous membrane or disturbances in their functions.

Acidity in the intestines

Normal acidity in the duodenal bulb is 5.6-7.9 pH. The acidity in the jejunum and ileum is neutral or slightly alkaline and ranges from 7 to 8 pH. The acidity of small intestine juice is 7.2-7.5 pH. With increased secretion it reaches 8.6 pH. The acidity of the secretion of the duodenal glands is from pH 7 to 8 pH.

The acidity of pancreatic juice is from 7.5 to 9 pH.

The acidity of colon juice is 8.5-9.0 pH.

In the lower parts of the colon, pH values of acidity gradually increase, reaching a maximum pH value in the region of the rectosigmoid junction.

Acidityfeces Normally pH is from 6.0 to 8.0.

Acidity of meconium (original feces of newborns)- about 6 pH.

Acidity of human breast milk - 6.9-7.5 pH

Blood acidity

The acidity of human arterial blood plasma ranges from 7.37 to 7.43 pH, averaging 7.4 pH. The acid-base balance in human blood is one of the most stable parameters, maintaining acidic and alkaline components in a certain balance within very narrow limits. Even a small shift from these limits can lead to severe pathology. When shifting to the acidic side, a condition called acidosis occurs, and to the alkaline side, alkolosis occurs. A change in blood acidity above 7.8 pH or below 6.8 pH is incompatible with life.

The acidity of red blood cells is 7.28-7.29 pH.

Normal blood revitalizes lymph cells that can destroy tumor cells. There are many lymphatic cells (eg NK cells, LAK cells) in the human body. Their uniqueness lies in the fact that they are able to distinguish normal cells from diseased and damaged ones, and destroy the latter. This is the function of the human body's immunity. The greatest activity of lymphatic cells in destroying diseased cells occurs at pH 7.4. However, usually around the affected cells, there is a more acidic environment, which interferes with the activity of lymphocytes, which work better at a slightly alkaline pH. By consuming foods that have an alkalizing effect, you can adjust the pH balance within 0.5 units, creating a favorable environment for the action of lymphocytes and the destruction of affected or abnormally constructed cells.

Cancerous tissue has increased acidity, unlike normal tissue, and the body protects it with a fibrous membrane whose pH is alkaline. If you continue to follow the acidic diet, the membrane dissolves and the cancer cells are released.

Once a week, when the body is acidified, it is advisable to arrange healing days for yourself, eating only vegetables (1.5 kg of vegetables, divided throughout the day), boiled and sometimes raw in the summer, only heat-treated in the autumn-winter) and Be sure to have clean hot water.

Equally important for maintaining normal levelspH The body also has a person’s mood; a good, cheerful mood normalizes the acid-base balance. Laugh more!

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As we all remember from school chemistry course, pH is a unit of activity of a hydrogen ion, equal to the inverse logarithm of the activity of hydrogen ions. Thus, water with a pH of 7 has 10 -7 mol per liter of hydrogen ions, and water with a pH of 6 has 10 -6 mol per liter. The pH scale can vary from 0 to 14.

In general, water with a pH less than 7 is considered acidic, while water with a pH greater than 7 is considered alkaline. The normal pH range for surface water systems is 6.5 to 8.5, and for subsurface systems it is 6 to 8.5.

The pH value of water (H 2 0) is 7 at 25 °C, but upon contact with carbon dioxide in the atmosphere, this equilibrium shifts to a pH of approximately 5.2. Because pH is closely related to atmospheric gases and temperature, it is highly recommended that water be tested as quickly as possible. After all, the pH of water is not a measure of the stability of an acidic or alkaline reaction and does not provide a complete picture of the characteristics or reason for limiting the water supply.

Soft water

In general, water with a low pH (less than 6.5) is acidic, soft and corrosive. Thus, metal ions such as iron, manganese, copper, lead and zinc from the aquifer, plumbing and pipes can leach into the water. Therefore, water with a low pH can:

contain elevated levels of toxic metals;
lead to premature damage to metal pipes;
have a metallic or sour taste;
dye linen;
have a characteristic “blue-green” coloration of the sink and drains.

The main way to solve the problem of low pH water is to use a neutralizer. It injects a solution into the water to prevent the water from reacting with your home plumbing or causing electrolytic corrosion. A typical neutralizer is chemical. Neutralization with this agent increases the sodium content of the water.

Hard water

Water with a pH above 8.5 is hard. It does not pose a health hazard, but may cause aesthetic problems. These problems include:

Formation of “scale” or sediment on pipelines and fixtures.
An alkaline taste in water that can make coffee taste bitter.
Scale formation on dishes, washing machines, swimming pools.
Difficulty in obtaining foam from soap and detergents and the formation of insoluble deposits on clothes, etc.
Reduced efficiency of electric water heaters.

Typically, these problems occur when hardness varies between 100 and 200 milligrams of CaCO 3 /L, which is equivalent to 12 grams per gallon. Water can be softened through the use of ion exchange or the addition of ash or lime/soda, but both processes increase the sodium content of the water.

pH of drinking water

Careful attention to pH control is necessary at all stages of water treatment to ensure satisfactory water quality and disinfection. Although water pH does not usually have a direct impact on consumers, it is one of the most important operational parameters of water quality. For effective chlorine disinfection, the pH should preferably be less than 8. The pH of the water entering the distribution system must be controlled to minimize pipe corrosion. Failure to do so may result in contamination of drinking water and adverse effects on taste, odor and appearance.

The optimum pH value will vary for different materials depending on the composition of the water and the nature of the building materials used in the distribution system, but most often it lies in the range of 6.5-9.5. Extreme pH values can result from accidental spills or breakdowns at wastewater treatment plants.

The ideal pH level of ionized water for long-term human consumption is between 8.5 and 9.5 (and never exceeds 10.0) with an ideal ORP value of around 200mV-300mV (and never higher than 400mV).

Pool water pH

As mentioned above, pH is the most important characteristic not only for drinking water, but also for swimming pools, since chlorination is still mainly used to disinfect water, and when using chlorine, the effectiveness of disinfection is highly dependent on the initial pH value of the water.

Chlorine is the primary disinfectant for preventing infections in public swimming pools, but chlorine also reacts with organic matter in the water to form disinfection by-products (DBPs): organic matter is a derivative of humic substances formed when water reacts with sweat, urine, hair, skin cells and residues of personal hygiene products released into the water by swimmers. DPP content can be measured as the sum of all halogenated compounds. Some DAAs increase the risk of asthma, are carcinogenic, or irritate the eyes and skin.

Chlorine is the common name for which produces chlorine gas when it reacts with water. When dissolved in water, the acid forms hypochlorite and has a pKa value of 7.5.

Chlorous acid is much more effective than hypochlorite, killing bacteria, cysts, spores and inactive viruses. Thus, if the pH value of a swimming pool is at the lower end of the control range, less chlorine must be produced for the same degree of disinfection, and therefore fewer potentially dangerous DBPs will form in the water. Numerous studies show that the optimal pH level of pool water is between 7.5 and 8.0. When the pH decreases by only 1-0.5 units (to 7.0-6.5), the level of PPDs, which are also genotoxic, increases significantly.

Methods for determining pH

The pH scale is a logarithmic scale, which means that every increase or decrease of 1 unit represents a change by a factor of 10. For example, a solution with a pH of 11 is 10 times more alkaline than a solution with a pH of 10. There are several methods for determining the pH of water .

pH determination using test strips

Test strips are litmus paper that reacts by changing color to pH fluctuations. You can buy them at pet stores, since they are often used to determine the pH of water in aquariums (even a slight fluctuation in this indicator can lead to the death of fish).

The test strip will change upon contact. You will only have to compare the final color with the sample color scale on the packaging and get a specific value. This method of determining pH is fast, simple, cheap, but has a fairly large error.

Rottinger litmus paper

Purchase from medical equipment stores in your city. Having analyzed various ph tests (from cheap Chinese to expensive Dutch ones), we came to the conclusion that the German Rottinger ph strips give the minimum error in readings. The package contains an indicator scale from 1 to 14 (the maximum available interval!) and 80 ph strips, which last for a long time. Using these strips, you can measure not only the pH of water, but also the pH of biological fluids such as saliva, urine, etc. Since good ph meters are quite expensive (about 3000 rubles), and for them you have to buy buffer solutions for calibration, Rottinger litmus paper, the price of which does not exceed 250-350 rubles, will serve you as an indispensable assistant in accurately determining the ph level.

Determining pH using a pH meter

A water sample (20-30 ml) is taken into a plastic or glass cup. The device sensor is rinsed with a small amount of distilled water and then immersed in the solution along with the temperature sensor. The instrument scale shows you the exact pH value of the solution being tested. It should be taken into account that the accuracy of measurements is affected by regular calibration of the device, for which standard solutions with a known pH value are used. This method of determining pH is accurate, simple, fast, but requires greater material costs compared to the previous one and simple skills in working with laboratory equipment and chemical solutions.

Thus, the pH of water is not just a term from a school chemistry course, but also an indicator of water quality that must be monitored to avoid problems with equipment and health.

We have already remembered or learned what pH is. We also know that pH is one of the indicators by which we can judge the functioning of our body and its health. And now we will learn how to quickly and easily determine the pH values of our body fluids at home. The simplest and also fairly accurate method for measuring pH is the litmus paper method. Litmus paper is a narrow strip of paper soaked in

litmus - a dye of complex chemical composition. Litmus paper is highly sensitive. Therefore, manufacturers place it in special small containers, usually made of plastic, which protect it from moisture penetration. For ease of use, litmus paper is most often found in these containers in the form of a small roll. By pulling the tip located in the so-called dispenser, you can tear off the required amount of litmus paper. This must be done with dry hands so that the paper does not react to the moisture of the hands. To obtain the result, you need to dip the paper into the solution for 2-3 seconds, and then compare it with the attached indicator scale, which is usually placed on the body of the litmus paper. What indicators can we measure at home? First of all, indicators of your biological fluids - saliva, tears and urine. It is better to do this in the morning, once after waking up. Please note that checking the pH of saliva and tears should be done before washing and brushing your teeth or rinsing your mouth. Water procedures will immediately make adjustments to the pH value, and it will not correspond to the actual acid-base level. Next, we can measure the pH of all the drinks we drink, the pH of tap water and bottled water if you drink it regularly. You can measure the pH of soups, tea, juices - freshly squeezed and from tetra packs, fruits, vegetables. You can measure the pH of all products that have a liquid component. We did this because it was interesting to know what foods and foods we consume, and what drinks get into our bodies. We didn’t just measure, we recorded the data in a notebook in order to have, firstly, our own database. And secondly, see the picture of pH changes over time. As it turned out, pH can change when the product is exposed to temperature and under some other circumstances. We have approached pH measurement with such interest and attention because it provides information about our acid-base balance. It also informs you about how food affects its level. Therefore, I recommend having this simple device in your household, which will become a reliable assistant in maintaining health.

If the indicators differ greatly, there is a high probability that the fish will not be able to live long in such conditions. To prevent this, it is necessary to check the pH level in the aquarium water. Let's try to figure out how to measure the pH level of aquarium water.

What are the ways to measure pH levels?

All the aquarist’s actions should be aimed at the comfort of his favorite fish so that they can feel very good. He needs to know in what environment a particular type of fish feels normal and, if necessary, be able to change it.

pH measuring tool.

The enemy of a neutral water reaction or an acidic reaction is the night, which is when algae actively produce CO2. You can achieve exactly the same result if you place the aquarium near a window where the sun's rays will directly penetrate it.

There are tests that can be used to measure the acidity of water. You can also purchase special electronic pH meters. All this can be found in aquarium stores. The tests are very easy to use and not expensive. As for pH meters, they are not cheap, although they can give very fast and accurate results. Given the indicator, it is necessary to draw certain conclusions and take measures.

The importance of acidity level

What is pH? This is the acidity level, indicating the amount of CO2 present in the water. Depending on the decrease or increase in the concentration of a given substance in water, you can determine whether the water is acidic (when the pH is greater than 7) or alkaline (when the pH is less than 7).

In an aquarium, carbon dioxide is produced by both fish and algae. In addition, other chemical reactions occurring in the aquarium can also provoke a deviation in the pH level.

If there is a sharp decrease or increase in acidity, it will be difficult for the fish to tolerate it. This is explained by the fact that each type of fish in nature had certain conditions in which they lived and reproduced. That is, they had water of a specific composition, and when a sudden change occurs, the fish, of course, do not like it. It is necessary to constantly monitor the pH level of the water in the aquarium and try to maintain it at a safe level.

A device for measuring water hardness.

Reducing the hardness of aquarium water

It is also very important to control the hardness of the water in the aquarium. If it is too harsh, then you will have to take a number of measures to soften it. What can be done for this?

You can dilute the source water with a small amount of distilled water. It is much softer, which will help soften the harshness.
Application of ion exchange resins.
Use of osmotic filters. Thus, you can try to make softened water yourself, but this is a very time-consuming task.
You can also reduce the hardness of aquarium water by using special substances with a chemical composition. They are sold in all zoological stores. Their use reduces rigidity.
Use of acrylic resins in crystalline form. They are poured into bags and lowered into the aquarium or mixed in a filter.
Aquarium plants such as aegropyla, elodea, chara plants and hornwort can also be used as water softeners.

Increasing the hardness of aquarium water

If the aquarium water has a sufficiently low hardness, then measures must also be taken. How to increase water hardness in an aquarium? This can be done with the use of magnesium or calcium. You can also simply add water that is harder in consistency.

You can also increase the hardness level by using baking soda. 0.3-05 g of this substance is enough for one liter. On store shelves you can find specially prescribed substances, with the use of which you can increase the level of hardness.

How to measure water hardness at home

To measure the total hardness of aquarium water at home, you need to remember a very simple method that involves using a soap solution. It is necessary to take calcium oxide (in an amount of 10 mg) and neutralize it in one liter of water with pure soap (0.1 g). You need to use laundry soap, it will help determine the hardness. Crushed soap (1 g) should be thrown into distilled water, preheated.

Half a liter of aquarium water should be poured into the flask and gradually add the prepared mixture there. Shake it all up. When bubbles are visible, this is a sign that the solution should no longer be added.

Hardness can be determined as follows: the soap solution in ml, which was needed for the fill, is multiplied by 2. If the experiment is carried out correctly, then only a small error can be made.

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