As far as I know....
Microbe/fungal life / health will naturally adjust pH around the root zone. Do you add or maintain your micro herd? Do you feed ro water with high salt nutes. Do you buffer your nute resevoir with a micro or cal mag?
The drip clean is messing up your ph. Just like flushing agents mess up ph for reuse so is the drip clean. Flush with molasses and 2.5 ml per gl of epsom salts. And start off slow with nutes. How close are your lights to the canopy ?
Yes. Epsom salts are commonly used to supply magnesium. Another good choice is Potassium Magnesium Sulfate AKA Langbeinite, KMag, or Sul–Po–Mag. Both are totally natural (organic) and quite soluble in water.
hey I know its an older thread but drip clean is only supposed to be at .4ml per gallon. I have used it higher for flush but when I have accidentally added to much I have had lots of weird lockouts. I think using to much could effect nutrient uptake. something to consider if you cant figure out the issue.