okay...imo, those chemicals are buffered in your soil and can screw with your ph.
...I would get yourself some rapid release dolomite lime, add 1tbls per gallon of soil as a top dressing and water it in as normal....
...I'm not claim'n this will fix your problem, but it's a good place to start... you really can't determine your soil's pH by it's runoff. Your nitrogen could be locked out due a pH issue....the dolomite lime will not harm your plant what so ever, it only tries to keep your pH in check for you...while giving you cal.
...once you know your pH is in range, watch for them to bounce back.... then try fertilizing. Good luck.