In most hydroponics systems and during most phases of growth, pH typically rises with your reservoir over the course of 2-7 days. So, you always need to readjust the levels of your reservoir. With this in mind, it is also advisable to allow a good pH swing in your reservoir, for example, if you want to maintain the reservoir’s pH level at 6 to 6.5 then you can easily afford to lower the pH to 5.8 and allow it to swing all the way to 6.7 before knocking it back to 6. Therefore, it is not recommended to change the pH unless it actually needs it.

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