Like I say, I'm no hydro guy (but I do work with coco) & this is the bit that confuses me... people always talk about the end point of EC... but never about the start point of their water!
Most guides seem to assume a tap water EC of around 0.5 mS/cm... but not everyone has that sort of water With a 0.09 Ms/cm, the feed is a bit like treacle to your plants
In coco, I would flush to reset things... but I have no idea how to do that with your setup
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