Buildup of nutrients can cause a drop in ph among other things like microbe respiration or death. Especially nutrients with a higher ammonium source of nitrogen.
Ph of water in makes little difference unless using a pretty hard water.
The soil composition and buffering capacity play a huge role and so do the nutrients used and concentration as well as microbes.
If using a decent water source in soil I would be far more concerned about the ph in the media rather than the ph of your nutrient solution.
It's covers more than you need but will help you understand the how ph works... its all about alkalinity.
OK I'm going to do my best to explain PH since its something that is for the most part greatly misunderstood and can be confusing to new growers and even experienced growers alike. This will explain why we need both ppm and PH meters to give us informed information about PH This will be a...
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