well, the ph was checked and found to be at about 5.1-5.2 so some hydrated lime was added to get it at about 5.8-6.

Could this have been a cause?

The reason this wasnt noticed is because generally the ph was too high and would only go up. This is the first time it has been too low or gone down. Must get back on the ol ph checking tradition.

They were pretty darn dry after not watering for a full 24 hours, but the condition didnt get any better.