Hydroponics is the cultivation of plants without the use of soil. This hydroponic system promotes rapid growth, higher yields, and superior quality.
If you’re into hydroponic gardening, you’ve wondered what kind of water supply to use. Most people use tap water, but they do not suspect that tap water can harm the quality and health of plants. Household tap water contains several chemicals and minerals that can harm plants. There are ways to test and treat tap water to make it safe for plants.
Let’s find out in detail what is the best water for hydroponic growing.
Contents
Water as a source of plant nutrition
Water is one of the main factors determining the vital activity of plants since it is water that takes an active part in all vital metabolic processes.
It performs many important functions:
- Transfers hydroponic nutrients to the roots and tissues of the plant
- Interferes with the overheating of fabrics and destruction of proteins
- It is a source of hydrogen, which is so necessary for the process of photosynthesis
Water is the regulator of all physiological functions of plants and even their very life. Water is a universal solvent, due to which all substances that come with water in a dissolved form do not lose their beneficial properties and do not change their chemical composition.
It is based on this property of water that nutrient solutions are prepared in hydroponics. But, is all water suitable for the preparation of nutrient solutions?
First, let’s look at the requirements that water used in the hydroponic cultivation of plants must meet.
- The content of salts and minerals in the soft water should be minimal. Water should be soft, and free from calcium and magnesium salts.
- The presence of toxic impurities, foreign inclusions, and plant poisons is unacceptable;
- The reaction of the medium must be neutral or slightly acidic.
In this case, what water is suitable to tap, from a well, river, or lake, rain or distilled? Naturally, each type of water has its characteristics, which indicate the degree of its suitability for the preparation of a nutrient solution.
Types of water usable in hydroponics water
Tap water
Tap water is often suitable for hydroponics water. In the United States, it has an average TDS (total dissolved solids) of 350 ppm (parts per million), making them safe for humans and plants.
Tap water flows from taps and is often supplied directly by local water utilities. Tap water is generally clean and suitable for most purposes due to the chlorine treatment and filtration applied to it. However, some locations may have tap water with TDS above 500 ppm, which can be a concern.
Note. If you’re unsure about the quality of your local tap water, an easy and effective way to lower your TDS levels is to install an activated carbon filter. Tap water is physically filtered through an activated carbon filter, resulting in cleaner water.
Components of tap water that affect hydroponics
Chlorine and chloramines
The most common problem with tap water is chlorine in the local water supply. Many water treatment plants have begun using chloramines instead of plain chlorine to kill bacteria in the water. Few growers know that chlorine is a trace element needed by plants. The fact is that it is needed in extremely small quantities, and it is not required to add it additionally.
Plants can absorb chlorine, they absorb too much of it from unfiltered water. As a result, plant growth slows down.
Chlorine also affects root health by killing beneficial bacteria and fungi. The microflora and microfauna that live in the root zone are important for plant health and allow for a high yield. Without microorganisms, the plant roots would not be able to obtain organic nutrients. Don’t let chlorine kill your plants!
Chloramines are chemical compounds of ammonia and chlorine that are often used as disinfectants in municipal water supplies. Chloramines do not evaporate from the water as chlorine does, and many water filters cannot remove them from the water. Chloramine is even more detrimental to your garden than chlorine.
To avoid problems caused by these chemicals, buy a filter that removes both chlorine and chloramine in drinking water. The health of the plants will improve significantly, and you will get a much bigger harvest afterward.
Mineral water
Mineral water is a suitable water choice for hydroponics. The TDS is at least 250 ppm, making it reasonably safe for humans and plants.
Most consider mineral water to be a healthier and cleaner alternative to tap water due to its natural origin and general lack of chemical treatment. However, mineral salts or microbes may still be present in the water.
Note: High TDS mineral water can be purified by filtration, reverse osmosis, zonation, or distillation. The simplest and most economical method is filtration, in which water is sieved through activated carbon filters.
Purified water
Purified water is potentially one of the best water choices for hydroponics with TDS levels below 10 ppm. Purified water is subjected to reverse osmosis or ozonation, which removes microbes, chemicals, and mineral salts.
Reverse osmosis water is passing raw water through a semi-permeable membrane that separates the water from unwanted impurities, mineral salts, or microbes. A reverse osmosis system can do a much better job of reducing the number of dissolved mineral particles in the water. But they tend to be expensive and can take a while to work.
Ozonation is an advanced oxidation process that uses ozone (O3) to remove microbes and other contaminants from water. Ozonation is more expensive and not as common as other methods.
Distilled water
Distilled water is pure water and the best choice for hydroponics with a TDS level of ~1 ppm. Distilled water is a water treatment process that has undergone distillation, as a result of which mineral salts and organic matter are completely removed.
Distillation works by boiling water until it evaporates and then collecting the condensed vapor. The boiling process kills germs and vaporizes contaminants, while evaporation ensures that mineral salts or other particulates are separated.
What kind of water is not used in hydroponics?
Wastewater
Wastewater refers to water used in homes, businesses, or industry and carried by sewer systems. Wastewater is unsuitable for hydroponics due to how unclean and polluted it is.
Wastewater can be treated, but such a process is too expensive for hydroponics. Using fresh tap water to replenish the system can be more cost-effective than trying to recycle wastewater.
Rainwater
Rainwater comes from natural rain that runs off catchment surfaces. It is not suitable for hydroponics due to possible contamination by microbes, small insects, pollution particles, or chemicals. Stored rainwater is a good place for microbial contamination or pest infestation.
Water from natural reservoirs
Least suitable for hydroponic growing plants due to a large number of impurities. It may contain industrial waste, decay products, and various pathogenic microorganisms. In principle, it can be used, but for this, it will be necessary to carry out a cycle of chlorination and settling.
Water treatment methods
There are quite a lot of them – the reason for this is the variety of various pollutants. However, according to the principle of action, these methods can be divided into four main groups:
- Physical or mechanical (settling, straining, filtering, and ultraviolet treatment)
- Biological (cleaning with activated sludge, sand, etc.)
- Chemical (reduction, neutralization, oxidation)
- Physical and chemical (return osmosis, sorption, extraction, flotation, ion exchange, thermal methods, and electrodialysis)
There are 3 main methods for purifying water:
UV treatment
It is used only for the destruction of pathogens, since it does not act on pollutants. The UV filter, which is a chamber with an ultraviolet lamp, destroys only living microorganisms.
Activated carbon filtration
Such filters trap many impurities by binding them to carbon. Often installed in front of reverse osmosis systems. It should be noted that not only absorbent carbon but also wood is used as a filtering agent.
Ion exchange
It softens water while removing organic compounds. Inside the plastic or steel housing, there is a filter tank with an ion exchange resin, which replaces the magnesium and calcium ions in the water with sodium ions.
FAQs
Is tap water OK for hydroponics?
How do you make water for hydroponics?
1. Buy nutrients.
2. Use clean water.
3. Mix salts with water.
4. Add trace elements.
5. Adjust the pH level.
6. Adjust the EC level.
Do you need purified water for hydroponics?
Can I use bottled water for hydroponics?
Conclusion
Before using water, you need to know the levels of chlorine, chloramines, and ppm in drinking water. To purify water from chlorine and chloramines, you can use any water purification process from harmful components.
Contaminated tap water is a major problem when growing plants. Therefore, to increase productivity, it is necessary to monitor the quality of water.
