I would try to maintain a ph of about 6.5 unless you were going fine with a ph of 6.0 if so then maybe we have another problem. If the plant is in its last stage of flowering ( last 2 or 3 weeks ) you will notice a yellowing of the leaves which is normal, but if it is something other than a gradual yellowing than we probably have a problem. Since your runoff is a low ph it makes me believe it is a ph problem causing this and i would flush straight away and not give any more nutes till harvest. ( if you are in the last stage ). They really start to fatten up in these last 2 weeks so i would get that ph right asap. Good luck

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I have never grown marijuana or intend to. Anything I post is knowledge gained from reading, not personal experience. Any pictures I post were aquired on the web or are fakes.