MrStinkyanswered grow question 3 years ago Yeah, what the others said - it is probably a pH issue - I wouldnt trust that meter for pH though (I had one years ago and it gave the same reading for soil at 4 6 and 8 pH) best to invest in a little yellow digital meter (and calibration powders) and pH everything going in to the soil.
You can test what pH the water coming out of the pot is too and see if it is too high / low.
If not pH then substrate could have too many nutrients.