pH & Nutrient Management

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The pH of your nutrient solution can seriously affect the availability of the nutrients in the solution - with certain nutrients ‘locking out’ if the pH fluctuates outside of optimal levels; even if there is enough of that element in solution, outside of the correct pH levels the plant will stop uptaking that nutrient. Novices often diagnose pH lockout as a nutrient deficiency but adding more of the locked out nutrient won’t make it more available to the plant and could potentially lock out other nutrients from its strong concentration. In hydroponic systems, it’s best to maintain a pH of between 6 - 6.5 to maintain optimal uptake while soil has a much larger acceptable range as the soil can buffer any added solution. For more info on pH and nutrition management, read our buyers guide below.

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Buyer's Guide

pH Nutrient Management

pH is the key that unlocks access to nutrients - without the optimal pH levels, the plant will be unable to access certain nutrients and if they pH continues to drift, more and more nutrients will be locked out.


The strength of a nutrient solution can be measured in several ways; with different regions and manufacturers using different scales to measure the same thing. Electrical Conductivity (EC) is a measure of dissolved salts in a solution - the more salt in a solution, the more easily an electrical current can pass through. A reading of 0 ec means there are no dissolved salts but you’ll likely have a base level of ‘limescale’ - which contains both magnesium and calcium carbonate. EC measurements are easy to convert to CF since a measure of 2 on your EC meter means there are 20CF.


EC and CF are the most commonly used units here in europe but there is a recent shift following the american market to TDS meters which is a measure of the total dissolved salts. Measurement devices read EC or CF and then use a rough, linear rule to convert it to parts per million (PPM), which is an estimation of the total weight of salts in a given volume of water, like a ratio.


In active hydroponic systems, you need to monitor your pH and EC by taking a reading of both every few days and adjusting it when it drifts outside of optimal levels. If you let your system drift from 6 to 6.5 before adding pH down, the plant will get a chance to uptake all the range of macro and micro nutrients.


You should feed your plants according to their needs - a young small plant won’t be able to uptake as much nutrients or be pushed as hard as a fully mature plant that's about to flower. Most growers have their best results starting a plant off at around 1 EC, including the base level of about .6 due to hard water. As plants mature you can slowly increase the concentration of feed in the solution. As you approach an EC of 2, be careful as over-fertilisation can have worse effects and be harder to treat than an underfed plant.


Keeping your hydro system within the optimal levels for both pH and EC will facilitate faster plant growth and larger yields.


If you've got more questions about pH or nutrient management, get in touch with our specialist team on 0800 085 7995 or email us.