BioThrive Fertilizer Water pH & PPM

you are in soil? 6.5-6.8 is argueably better. If the soil is taking the 4.5 you add and spitting out 6.7, how would adding a less acidic solution help you stay under 6.7? That would do the opposite of help. I'd hesitate adding anything more acidic than 4.5... pH scale is a log scale. As you get further from 7, the incremental differences represent much larger swings in H+ potential. If the soil does continue to push upward, that's when i'd slowly reduce pH again and see what happens. The soil may have been amended with too much lime or something... could be microbes... there's a lot of unknowns with soil. does look like a Ca issue.. which could be from too little Ca or too low pH of feeding solution... runoff pH and soil slurries are more of an art as far as interpretting them.. they are not accurate, but are precise. If you aren't adding +whats in soil 100ppm of Ca on average per irrigation (not just fertigation) you are probably fine. tough to know what is in the soil. easy to calculate what you supplement. Without know what's in the soil, it's just a guess to rule it out without trial and error.