You can test ingoing water with a freshwater aquarium ph test kit. ($7.00 US) I'd try and get one this weekend, and flush the excess nutrients with at least 5 gallons of properly ph'd water, (6.3 to 6.8 ph) and resume nutes on their next feeding day per the FF schedule.
Leaf damage is permanent and will look worse as time passes. New growth should be fine once you get your ph and nutes back under control.