Importance of PH and EC in hydroponics

Posted by grow-world 20/09/2016 1 Comment(s)

Importance of PH and EC in Hydroponics

It is surprising to see that PH and EC are most overlooked aspects in hydroponic and organic as well as regular soil gardening.The importance of PH and EC in hydroponics cannot be ignored. Therefore, we have to take positive measures to ensure that these two remain in a limited range .Today, at Grow World Hydroponics, we are going to tell you about the relevance of PH and EC in hydroponics and about the measures that should to take to maintain them. 

Starting with the technicalities; what are PH and EC? The term PH refers to potential hydrogen-hydroxyl (PH) ion content of a solution. A PH value from 1 to 6.9 is considered acidic whereas a value from 7.1 to 14 is considered alkaline. The PH of 7 is considered neutral and that is the PH of water. EC stands for electrical conductivity which measures the potential of any material to conduct electricity. 

Why is it important to maintain the PH and EC?

Maintenance of PH is imperative to your plant's growth. If you fail to maintain the PH of the solution then your plants will lose some their ability to absorb some of the nutrients which are needed for their healthy growth. The level of PH requirement varies from plant to plant but generally, most of the plants grow well in an acidic solution.  As the PH of the solution goes above 6.5, many nutrients and micronutrients precipitate out of the solution and stick to the walls of the reservoir. Plants only absorb nutrients that are dissolved in the solution and at a higher PH, they will fail to absorb the nutrients and suffer from multiple deficiencies.

It is equally important to maintain the EC of your hydroponic solution. A high EC in the root zone is needed by the plant to absorb more water and retain it for a longer time. EC not only is a measure of the amount of fertilizer given to the plant but also is a climate control mechanism relating to water absorption. Therefore, EC management is extremely central in terms of water absorption and retention. 


How to check PH and EC? 

Checking PH level of your hydroponic system is very easy as you have multiple options available. You can use a PH meter which will give you the exact measurement or you can also use a liquid tester that would show you the results based on color. Perhaps the easiest method is to check the level of PH using PH strips. They are pretty popular and widely available at stores. 

The Electric strength of a solution can be measured using an Electrical Conductivity meter. EC can be measured in a number of units but the typical unit is siemens per square meter per mole (S/m2/mole) or millisiemens per centimeter (mS/cm).The reading would be higher if the ionic strength of the solution is higher. Hence, EC would also be used to check for the solution strength.  The EC strength needed would depend on the growth stage of the plants. For guidance, a seedling needs between 0.8 to 1.3, a clone needs between 0.5 to 1.3, a vegetative needs 1.3 to 1.7 and a flowering needs 1.2 to 2 strength of EC. 

How to adjust for optimal PH and EC?

After measuring the PH and EC around the root zone of your hydroponic plants, you need to adjust their values up or down and reach the optimal PH and EC that are required by the plants.

There are several ways in which you can adjust for PH. Perhaps the most popular way to decrease PH is too add phosphoric acid and to increase PH is to add potassium hydroxide. There are many other chemicals that can also be used to adjust for PH if you are unable to find the ones mentioned previously. For instance, nitric or sulfuric acid can be used to lower PH but they are much more corrosive than phosphoric acid and therefore should be avoided at most. If you are not in favor of manual adjusting then PH adjusters can also be easily found at the stores. Automatic PH dosing pumps can be attached to PH adjusters which will control the level of PH by monitoring the solution constantly. Whenever these pumps detect that the PH level is out of the predetermined range, the will began to adjust the PH level. Similarly, EC can be adjusted for its optimal level by using EC adjusters. 


Grow World Hydroponics

Unit 3 620 Bristol Road South 



B31 2JR

0121 448 3155 

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1 Comment(s)

Lawrence Lomax:
16/12/2019, 02:13:22 PM

I have a TDS and EC meter combo, when I read the EC for water I get a reading of 0230 EC and the TDS is 104. On adjusting the pH to read 6.5 using nitric acid the TDS shoots up to 2052 and the EC wont read. Is this correct as on adding hydroponic salts 10gm per 5 litres I get a reading of 2233 TDS and the EC wont read. Many thanks in anticipation if you can help, Lawrence

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