Everything for horticulture Personal advice from our specialists Worldwide delivery of 30 000 products
Search your products below, and request a quote within 30 seconds
Shop  Knowledge center Fertilizers  General  How do you reduce the input of sodium in drain water?

How do you reduce the input of sodium in drain water?

reduce sodiumWritten by Jaap Lubbersen | Last update: 27-3-2020

The duty for water purification has stirred up the discussion about growing without emissions. The main reason for discharging water in substrates is the excess of sodium water. Excess sodium inhibits growth in many crops. Fertilizers are often considered to be the largest source of sodium input, while many other sources of sodium are present. Therefore, an overview of possible sodium sources is listed along with some tips how to limit the amount of sodium in waste water.

Irrigation water

It might seem obvious, but to avoid excess sodium, it is very important to use irrigation water with a low concentration of sodium.  Ground water, ditch water and tap water generally contain a higher percentage of sodium than osmosis water and rain water (note: the closer you are to the coast, the more sodium can be found in the rain water). 

Also, you can choose for an installation that filters sodium from the water. Thanks to an installation as such, you can make use of groundwater, ditch water and tap water, without an excessive presence of sodium. 

Organic substrates

Organic substrates – especially the ones containing coconut – can contain a high percentage of sodium. If making use of a coconut substrate that was not buffered and rinsed thoroughly, a high amount of sodium can be remain. It’s important to take this into account when choosing a substrate. You can decide to be advised by a certified substrate supplier.

Chlorine-based disinfectants

Many chlorine-based disinfectants contain sodium (chlorine is part of sodium chloride). It is recommended to use disinfectants free of chlorine, when you want to limit the amount of sodium. A chlorine-free disinfectant of good quality is Huwa-San.

Plant enhancements

Instead of using crop protection products and/ or fertilizers, you can use plant enhancers to strengthen the defense mechanism of the plant, meaning a better resistance against diseases. However, these products consist of natural raw materials and therefore contain sodium.

Organic fertilizers

Earlier, we mentioned that fertilizers aren’t always the largest source of sodium presence in water. However, they do play a role. This is particularly the case for organic fertilizers. They are entirely made up of natural raw materials of plant or animal origin. The durability and environmental friendliness aspect of these fertilizers is an advantage of the products. 

You can reduce the amount of sodium originating from fertilizers, by carefully selecting the most suitable one for your growth. By choosing a cleaner brand, sodium levels can be lowered. An example of this is a simple adjustment to the recipe that we generally advise. This is the conversion of the iron supply from a DTPA 3% (basic sodium) to a DTPA 6% (basic ammonium). The DTPA 6% iron is completely sodium free and therefore particularly suitable for recirculation. The nutrient recipe can be composed of fertilizers not containing sodium. In addition, our specialists would be happy to help you with a personal composition of nutrients. 


Hopefully this article has contributed to your awareness about possible sodium sources. This does not mean that we discourage the use of chloric-based organic substrates, fertilizers, plant enhancers or disinfectants!

Any questions about reducing the input of sodium?

Do you have any questions about crop care, or do you want personal advice? Contact one of our product specialists, or use the form below. 

Contact form

Jaap Lubbersen About Jaap Lubbersen

Jaap Lubbersen is an internal crop care product specialist at Royal Brinkman and has had over 13 years of experience in glass horticulture. "As an internal product specialist, I deal with growers' issues on a daily basis. Every time again it is a challenge to seek the proper solution, in cooperation with the grower, whether it is about healthy and vibrant cultivation, legislation or safety."

Do not delete this link