How To Maintain Ph Balance In Hydroponics

by RightFit Gardens | Last Updated: July 10, 2021

Inexperienced growers are often confused when they hear terms associated with the system. Even though it may not be easy to grasp initially, pH is something that can be learned in theory.
To keep the pH levels stable, indoor growers can take a few steps and exert some effort. Understanding these points is essential.

Immediately upon learning what pH levels are, you realize that they will never remain stable by themselves. Many external factors will influence the pH level, and there are too many variables.
The process of monitoring and altering your system’s pH does take some effort; however, once you are familiar with the fundamentals, it isn’t as difficult as you think. To know what pH means to your plants and how it can affect their healthy growth is the first area you need to understand. Next, we’ll explore how pH affects your system and what you can do to maintain proper pH levels.

What is pH?

ph level hydroponicsThe scale starts at zero and runs up to fourteen. There will be a different reading for every liquid on this scale. Depending on where it comes from, plain water has a different pH level. In many cases, it is better not to use tap water when it is possible since it will have a different pH value than the water in your system.

The scale has zero, which is the most acidic and finishes at 14, the most alkaline. Almost everything that lives likes a balanced ratio, so around the seventh mark. Not only does this pH level provide good starting conditions for optimal growth, but it is also an appropriate pH for human health.

For plants to flourish at their best, pH levels should be around 5.5 to 6.5. However, some plants and vegetables prefer to have a pH of 8 rather than neutral. An alkaline compound consists of potassium and sodium carbonate, which are soluble salts. Alkalinity refers to the level of alkali in the solution.

When your system has a favorable pH level, your plants will be able to absorb all micro and macronutrients through their roots. Additionally, you see faster growth in your plants because they have more NPK (Nitrogen, Phosphorous, and Potassium) available to them. It’s important to note that the closer you get to either end of the scale, the more liquids will burn. The pH level of any solution does not matter whether it is acidic or alkaline, so you need to be cautious.

What is the significance of pH levels in hydroponics?

In our experience, plants are at risk of not absorbing enough essential plant nutrients when pH levels are out of range. Furthermore, it can also help you determine whether the salts in your nutrient mixture are soluble or not. Minerals have varying tolerance levels for pH. Macroscopic nutrients are needed in high quantities by plants. In an environment with an inappropriate pH level, these become immobile and unable to absorb nutrients, causing them to become deficient.

In contrast, micronutrients need to be consumed in smaller quantities. A pH difference of either extreme will affect these. In low pH environments, plants can easily absorb too many nutrients, as they are highly soluble. Plants aren’t deprived of nutrients in this way; on the contrary, they are flooded with a toxic solution. Nutrient deficiencies can occur if your pH is too high.

To ensure your hydroponic system is pH balanced, you must first understand the elements that will affect pH levels.

Growing Medium

The pH level in your system can be affected by almost anything. Your growing medium will be one of the most critical aspects. Calcium-containing rocks are a good example, as they release magnesium into your hydroponic nutrient solution. You will need to adjust as soon as they leech into your water. Fortunately, this isn’t a common growing medium.

The salt concentration present in coco coir can affect pH. As a result, this must be rinsed thoroughly to remove any residual contamination.

Perlite is another common growing medium. As its pH ranges between 6 and 8, it can be added without significant pH swings. Another favorite is Rockwool, which has a pH between 7 and 8.5. There is some washing involved before use and some pH adjusting once it is in your system.


The water temperatures should be around an optimal range of 65 to 80 degrees Fahrenheit, but we don’t need to go into too much detail. The water will evaporate faster than the mineral salts if it gets much warmer than this.

After this occurs, algae begin forming on the reservoir’s edges, increasing the ratio of nutrient levels to water. In addition, small reservoir systems often suffer more than larger reservoir systems. Depending on your area, you may need either a water heater or a water cooler to keep the mix at the right temperature.

Plain Water

A sterile environment is crucial for hydroponic systems to function correctly. Due to the amount of treatment it has undergone, drinking water from the faucet is not recommended. There can be different types of water in different regions, so the base pH will never be the same everywhere.
It is recommended to use distilled or reverse osmosis water whenever possible. It is possible to purchase reverse osmosis kits that sit inside your plumbing system if this is not readily available. It may seem that these are small investments, but over time, they pay for themselves.

Setting up Your Hydroponics System Properly

It’s finally time to test your pH levels and get your hydroponic system running before adding plants to it, so learn all the reasons why pH levels affect your hydroponic system.  Since pH testing isn’t a one-time event, the following is still applicable if you are still researching. If you do this every day initially, you will gain a better understanding of how your system works. There are various ways for you to test the pH levels of your water. It is possible to quickly determine if the levels need to be raised or lowered using litmus strips or digital testers.

Hydroponic nutrients can also come with pH buffers, which is one thing to note here. Plants won’t undergo a sudden change in level as a result of this. Even though you must still adjust, you will minimize the extent of your actions.

Litmus Strips

Testing pH in your system with litmus strips is one of the easiest and fastest methods. While they are convenient to keep on hand, you shouldn’t rely on them without another method of measuring. There is a dye in the paper that reacts to any liquid it’s in contact with.

You can test your water system by collecting a sample and storing it in a sterile container. Wait until the color changes when you dip one of the paper strips into this. Using the litmus pH testing kit, you can compare the results with the chart once there are no more changes.

Guessing the colors can be challenging, as some of the colors are hard to distinguish from one another. This slight difference may not seem significant to many plants, but to those that require tight tolerance, even this tiny change can have a significant impact.

Also available are liquid test kits, which work the same way. Adding dye to the sample starts the process of color change, then the sample is compared to your color chart once the pH-sensitive dye is applied.

Hydroponic pH Pens

Despite being the most expensive option, this is not overly expensive, and it can last much longer than your litmus test kits. Additionally, you will have a digital meter, so it’s impossible to make a mistake.

The digital pH pen is one of the most common designs. You get an accurate reading when you place the nib into your water sample, which is very accurate. The downside of these pH pens is that their readings may fluctuate over time, so your pH pen needs to be calibrated. This can be a weekly task if you do a lot of testing.

You can find out how to test your water’s pH in our complete guide. Understanding the whole process will help you keep your plants healthy.

Consistent Water Treatment and pH Balancing

We’ve now discussed the equipment you need to use to test your nutrient solutions; now, let’s talk about how the pH levels of different types of systems can vary. As the solution directly contacts the plant roots, NFT (Nutrient Film Techniques) is one of the more straightforward techniques.
Readings from media-based systems may differ in one direction or another. Due to this, you must take two separate readings. As a first step, you should take a hydroponic solution from the reservoir and a chemical solution from the leachate.

The reason for this is that you will have different readings before and after the rooting process. Depending on how many plants you have, this may not vary too much; however, the variance can be much more significant if you have a large garden.

When adjusting the pH levels of your solution, look at the readings from the runoff solution that you come up with, and then adjust the pH levels in the reservoir accordingly. It is necessary to do this because the pH levels in the solution that passes through the plant’s roots will be higher than those in the reservoir.

Managing Your Hydroponic pH Levels

Various factors can affect your pH level. It is fortunately easy to fix some of these. When you purchase essential nutrients from a reputable supplier, they will also come with pH buffers.
Buffers are great for preventing spikes or drops which may shock plants. In addition to this, you can also purchase the adjustment product from these suppliers. There are pH UPs and pH downs available for purchase. Because pH sensitivity exists, you may need to take separate readings and follow recommendations if you need to re-adjust the dose.

As necessary, repeat these steps until you achieve the required level. Avoid adding more chemicals to achieve faster results. If you swing too far from one direction to the other, your plants may be shocked.

When adding new nutrients, the pH levels in your reservoir will change, so you will need to conduct a new test when you add these nutrients. Apart from that, it is a good idea to run your tests daily at the same time. Several natural methods can adjust your pH if you have no pH Up or pH Down.

The above method is a very short-term solution and should only be used in an emergency. Baking soda, nitric acid, potassium hydroxide and phosphoric acid can raise the pH levels. On the other hand, weak acids like white vinegar or citric acid can reduce it. It is essential to know exactly how much has changed over time for the amount you are adding.

A Brief Summary

In summary, let me summarize what we have discussed so far. If you follow these steps, you can maintain your pH levels and have plants that thrive.

Harvest time will bring the best crops for growers who know their hydroponic garden’s needs and maintain them. This can be catastrophic for growers who think it’s unimportant.