If the new ones are burning tips I would cut back more on the nutes. Maybe they just don't like as much. I have heard of a few strains like that. OH, you need to have the well water tested to see I bet that's it. Something in the water. You need RO water and calmag+ and B-52 or liquid Karma.to put back what you need. Might not be chlorine, could be iron or something like that. You never know till you test. 200 is hard water but I have seen prob's with water at 100 TDS.