Hydroponics has become a popular method for cultivating plants in recent years. Unlike traditional horticulture processes, hydroponics, a subset of hydroculture, grows plants without any soil. This is achieved by using mineral nutrient solutions in a type of aqueous solvent. 

You may have come across the abbreviation “EC” when dealing with hydroponics. “EC” simply stands for “Electrical Conductivity.” In other words, it refers to the potential of any material that conducts electricity. 

Most hydroponic growers measure their feed amount in ounces per gallon, grams per liter, or in other units of measurement. EC goes one step further than all of these. It measures the potential for an electrical current to travel through water. 

If you’re a hydroponic grower, it’s important that you understand everything about EC as well as why it matters. That is why in today’s article, we will be discussing EC and why it’s important in hydroponics. 

EC (Electrical Conductivity) 

EC, in hydroponics, is a measurement of electrical conductivity within a nutrient solution. It can also be shown as CF or Conductivity Factor. 

While checking pH levels can give you a good idea of the balance of available nutrients, EC gives you an indication of the number of available nutrients.

There is no electrical conductivity present in pure or distilled water. This is because they do not contain any kind of minerals. It’s when minerals are added to water that the dissolved salts allow the water to conduct electricity. The more salt there is, the higher the electrical conductivity will be.

When you measure this conductivity, you can find out how many nutrients there are in the water. With most plants, your EC measurement should be between 1.2 to 1.6 during their vegetative state.

During flowering, plants should have a reading of 1.6 to 2.4 but the type of plant can determine this measurement. For instance, tomatoes can handle an EC of up to 2.8 whereas basil can only manage 1.4. Spinach, on the other hand, can reach as high as 3.5.

Is EC Important In Hydroponics? 

In short, yes, EC is very important in hydroponics. When you measure the EC, you can achieve a more detailed idea of what is happening inside your nutrient feed. This gives a more accurate reading and more detailed information than a regular pH reading.

Over a period of time, your EC readings will either remain the same, go up, or go down. This is why you must measure your EC frequently. 

If the EC measurement remains at the same level, it means your plant is using as much water as its nutrients. Therefore, it’s balanced.

You should always ensure that the nutrient tank is topped up with a solution of this equal strength. This is to keep an ideal balance. Just check regularly to make sure everything is working as it should be. 

If your EC measurement goes up, it means that your plant is using more water than nutrients. Therefore, it’s not taking up a sufficient amount.

In this instance, you need to add more water to dilute the solution. If you see burned tips of leaves and a slower growth cycle, this can be tell-tale signs of overfeeding. If so, the nutrient solution would be too strong for the plant.

If your EC measurement goes down, it could be an indication that your plant is using up more nutrients than water. If this happens, you should top your nutrient solution back to what it was before. You could even try a stronger nutrient solution feed.

Just be careful if you’re increasing the strength by watching the EC closely so you can inspect how the plant reacts to the change. 

Temperatures can also have an impact. On humid or hot days, your plants will probably soak up more water.

You should change your nutrient solution frequently. If you don’t, your plant could be at a higher risk of increased toxic nutrient levels.

While EC measures the number of nutrients available in the water, it will not tell you how much of each element is in there. That is why it’s possible to have the perfect EC measurement but continue to experience nutrient deficiencies.

Unfortunately, EC also doesn’t inform you if different elements or waste have built up to harmful levels which can damage the plant further. 

Measure the conductivity every day if possible. Top up the nutrients when necessary and perform a nutrient refresh every 7 days. Do this by emptying your tank and then create a new solution from scratch. 

How Do You Measure EC?

It’s all well and good knowing what EC means in hydroponics but you need to understand how to measure it. The simplest way to do so is by using a digital meter.

A Bluelab CF Truncheon is a great example. These contraptions work by measuring the electrical conductivity through electrodes located on the base of the meter. You just have to dip this end into your solution and then check the digital reading. 

You should measure this conductivity every day. This is so you can keep a close eye on what is happening and if anything needs to be changed. As you know, things can change each and every day when growing with hydroponics. Therefore, you will want to catch and be aware of any potential issues as soon as possible. 

We highly recommend regular cleaning, calibration, and general maintenance of your EC meter. This is the best way of ensuring it always delivers accurate readings.

If you’re unsure of how to do this properly, you can head to a local hydroponics store (google online) and a member of staff will assist you with a calibration service. These are usually free but it completely depends on the establishment you use.

In Summary 

EC is not only a unit for measuring the fertilizer given to plants but it’s also a climate control device relating to water absorption.

When you start to grow plants, they should have a low EC. This should build up as quickly as possible for the plant to receive sufficient nutritional requirements and to raise its internal osmotic value. The result will be a stronger and healthier plant.