alltatup I don't believe I have intentionally made the pH fluctuate before, since I never tested the pH of the tap water before I started added nutrients (though our tap water's pH is about 7.3-7.5 usually). But then when I started adding the nutrients, I made sure to pH the water to about 6.5 and have been giving water and nutrients at 6.5 since then. I am not sure what caused that the Gorilla Zkittlez's pH to go all the way down to around 5.0 pH?