... no need
Z_Bop, it is a good example of how cumulative inputs can drive the pH down, along with up'ing the ppm's/EC,.. one thing that can bite back before too long! Finding "just right" on that is no small thing,... one reason folks like to go organic, where the cumulative inputs form synthetic nute salts isn't an issue,....
to give you an idea about how different pH availability is between soil/soilless and hydro', check out these charts-->
>>> mcpd-- great! If you weren't in bloom, foliar spraying would be a good way to go for fast results, bypassing the soil while you get that dialed in,,, but mold and residues are an issue during bloom, so that's out for now,.... try that water only run-off pH reading, it can offer a clue at least... a TDS/EC reading too if you can,...