Lets say I got a few drops of general hydroponics pH testing solution in a gallon of water with nutrients... Will that harm a plant? What is in the solution anyway? I can't seem to find any information on it. Thanks
Likely one of these... pH indicator - Wikipedia, the free encyclopedia 'Azolitmin' has the proper color change over the right range for that kit, but don't know if it comes in liquid form as well as in litmus paper. Could be one of the other ones too. In any case, they are mostly organic compounds, and I strongly doubt a couple of drops will have any affect on any thing.
I toss my extra water after testing into a potted plant .. no problems, been doing it to the same palm for 3 to 4 years....