The ph-value is a important adjusting screw in hydroponic cultivation. Only those who pay attention to the ph-value will reap the highest yields. Therefore, you should know the most important facts about ph in hydroponics.
This article answers your questions about ph-value in soilless cultivation! If your question is not included, write it in the comments below!
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What is the ph-value?
The ph-value is a measure of the acidic or basic effect of a solution.
"ph" means pondus Hydrogenii (lat. pondus = weight; hydrogenium = hydrogen) – the weight of hydrogen.
The ph-value therefore describes the quantity of hydrogen ions (H3O + ) in a solution. hydrogen ions are positively (+) charged. The antagonists of the hydrogen ions are the hydroxide ions (OH – ). These are negatively (-) charged.
The ratio of hydrogen and hydroxide ions determines the ph value.
The ph-value is measured on a scale from 0 to 14 shown.
If the ph-value is less than 7, the solution is acidic. hydrogen ions (H3O + ) are more concentrated than hydroxide ions (OH – ). At a ph-value greater than 7 the solution is basic. hydrogen ions (H3O + ) are less concentrated than hydroxide ions (OH – ). At a ph-value equal to 7, the solution is ph-neutral. Hydrogen and hydroxide ions are equally concentrated.
The basic or. Acidic effect increases starting from ph 7.
As you already know, the ph-value indicates the concentration of hydrogen ions (H3O + ). These are so numerous that it is impractical to express them in absolute numbers.
Therefore number of hydrogen ions/protons (decadic/decadic) logarithm. If the ph-value changes by one unit, then the concentration of hydrogen ions has changed tenfold.
By the way: the ph-value is often described as the negative decadic logarithm of the oxonium ion concentration defines. Oxonium describes protonated water (H3O + ).
Why is ph-value so important in hydroponics??
The ph-value determines the availability of nutrients to the plant.
Depending on the ph-value, nutrients are better or worse available for the plant.
In hydroponics, the optimum ph value is sought by matching the nutrient availability to the nutrient requirements of the plant!
If this is not the case, deficiency symptoms and/or toxicity are imminent. For example, many plants develop magnesium and calcium deficiencies at ph levels below 5. On the other hand, a ph-value above 6.5 lead to iron deficiency.
The chart shows the availability of most nutrients at different ph-values. However, the nutrient availability is dependent on further factors. The chart is therefore inaccurate and only serves as an illustration.
What is the optimal ph-value in hydroponics??
In hydroponics, ph-values between 5.5 and 6.5 are optimal for most plants. Most nutrients are best available to plants in this pH range.
The optimal ph-value depends on the plant. For example, blueberries require a ph value of approx. 4.5 – 5.5. Lavender or mint, on the other hand, prefer ph values of 6.0 to 7.0. A pumpkin is again with a ph-value of 5.5 to 7.5 relatively undemanding.
Plants in hydroponics need different ph-values than plants in soil. Ph-values for plants in soil must not be transferred to hydroponics. In soil, microorganisms, organic material and interactions between minerals and water regulate the ph value.
What is used to measure ph in hydroponics??
The ph-value of a nutrient solution is measured by means of a ph-meter.
The measurement by ph-meter is electrochemical. The electrical potential of the glass electrode depends on the hydrogen ion concentration. From the potential difference to the reference electrode, a voltage is generated which (relatively) linearly maps the ph value. The reference electrode is i. D. R. A silver-silver chloride half cell.
At regular intervals, the ph-meter is filled with a calibration solution calibrated. The calibration solution can be purchased online and has i. D. R. Ph-values of 4, 7 and 10.
- Easy calibration with automatic buffer detection
- Automatic temperature compensation (ATC) (in the range 0-50°C)
- Large LCD displays ph value, temperature as well as calibration status
- ✔【fast and accurate】– make sure your pool, the general.
- ✔【automatic temperature compensation】– you no longer have to worry about.
- ✔【wide use – pocket size ph meter】– is the ideal test kit.
Furthermore, the ph-value is calculated with acid-base indicators measured. However, measurement by means of color indicators is comparatively inaccurate and more complicated to handle.
How to lower the ph of a nutrient solution?
The ph value is measured with medium resp. Strong acids lowered.
Suitable acids for lowering the ph value:
- Ph-down
- Nitric acid
- Phosphoric acid
- citric acid
For beginners and advanced users ph-down is suitable – a prefabricated ph-lowering agent. The ready-made mixture is easy to use and also has a ph buffer.
To lower the ph, acids that have plant nutrients are recommended. Use nitric acid when growing and in the flower phosphoric acid. Citric acid is suitable as an organic acid.
Ph-down in growth:
- ADVANCED HYDROPONICS ph- lowers the ph-value
- REGULATES (lowers) the ph-value and ensures that the nutrient solution resp.
- EFFECTIVE lowering device which is used during the growing phase
Ph-down in bloom:
- 1 liter "ph down bloom" from advanced hydroponics is used during the.
- It regulates (lowers) the ph-value and makes sure that the nutrient solution is.
- This ensures that plants receive exactly the right nutrients.
When dealing with highly concentrated acids, the following applies: "first the water, then the acid, otherwise the monstrous will happen"!
How to increase the ph-value of a nutrient solution?
Strong bases increase the ph-value.
Appropriate bases to increase ph:
- Ph-up
- Potassium hydroxide
- Potassium carbonate
Here, too, a ph-up is recommended for both beginners and advanced users. This can be especially handy if too much ph-up has been added.
How to adjust the ph value in hydroponics?
The ph value is measured in 5 simple steps.
- Measure the ph-value
- Add ph-down if ph-value is too high. Add ph-up if the ph-value is too low.
- Mix the nutrient solution
- Wait ca. 10 min (for more accurate measurements; optional)
- Measure ph again and adjust if necessary. Again on.
How to measure and adjust the ph value automatically?
Automatic measuring and control equipment measure and adjust the ph-value.
This requires fertilizer computer with corresponding pump technology. The computer measures the ph value with a ph probe. After entering the desired values, the computer adds an acid or a base via a pump.
On the one hand, some devices measure only the ph- and/or the EC-value. On the other hand, some instruments adjust the ph and EC values accordingly. In most cases the temperature is also measured. A selection of suitable and high quality measurement and control equipment is shown below.
Device for automatic ph-, EC- and temperature-measurement:
- Permanently installable meter for measuring ph-value, temperature and (tds) EC.
- Make simple two-point calibration and automatic temperature compensation.
- 24/7 monitoring of nutrient content and ph-value for optimal.
device for automatic ph and temperature measurement and ph adjustment (connect).
- Doses ph up or down – use with undiluted bluelab ph after.
- data logs on your computer – compatible with bluelab connect.
- Automatic control and monitoring of the system ph with reservoirs up to.
Why does the ph of a nutrient solution vary??
The pH value of a nutrient solution is influenced by temperature, substrate, nutrients, plants, rain, algae and microorganisms.
Ph-value fluctuations indicate too low buffer properties your nutrient solution. Stabilize the ph-value with a ph-buffer. after that the fluctuations should be much less.
Nutrients are usually slightly acidic. Plants the nutrients are consumed and the nutrient solution loses some of its acidic effect. The ph-value increases.
At a high temperature Increased CO 2 gas emissions from the nutrient solution. Thus a (very) slight acid leaves the nutrient solution. the ph value is increasing.
substrates have their own ph-values. When substrate and nutrient solution come into contact, the substrate will affect the ph of the nutrient solution. For example, rockwool has a high ph of approx. 7.5 – 8.5.
Rain acts acidic and can also affect the nutrient solution in an outdoor hydroponic system.
Algae influence the ph-value by consuming carbon dioxide during the day. during the day the ph-value can rise and during the night it can drop again – even if slightly.
Dead organic material is decomposed by bacteria. Acids are released in the process.
How to stabilize the ph-value?
In hydroponics, a ph buffer stabilizes the ph of a nutrient solution.
A buffer is a mixture of a weak acid and its corresponding base or a weak base and its corresponding acid.
Each ph buffer has a buffer capacity. The buffer capacity describes the amount of acids and bases that a buffer solution can absorb without a significant change in the pH value. The ph buffer balances an alkaline or acidic effect.
Ph-up& ph-down not only lowers/increases ph, but also has ph buffering properties.
What do I have to pay attention to with tap water??
The carbonate content of the tap water influences the ph-value.
check the carbonate content of the tap water with your local utility company. Carbonates have a basic effect and thus increase the ph value.
When the level of hydrogen carbonate (HCO3 – ) exceeds 75 ppm, the ph value increases.
you can lower the alkaline effect with ph-down or by reverse osmosis. Water is forced through a semipermeable membrane by a hydrostatic pump.