I just use distilled water that has a ph of 6.5 and add all nutes as follows(quater to half strength) advanced nutes iguana bloom,foxfarm kangaroots bushdoctor(which is lots of bacteria,microbes,fungi etc...),voodoo juice, b-52,bud candy(carbs to feed soil),Hygrozyme(ezymatic formula),just started using humbolts snow storm ultra,and in week 5 and 6 flower i will add overdrive then allow three weeks flush and harvest hopefully by week 9.I just use droplet solution for ph and I dont have a ppm meter, dont really need one cuz just by looking at your plant you should be able to tell what she needs.Tips burning with random spots on leaves is too high ppm another sign is the serreated tips on the leafblade will rise upward like symptoms of heat stress, but its overfert. chemical or organic if you overfert and dont flush, your buds gona taste shitty and crackle when lit.