FAQ: Is it possible to overdose Seachem Alkaline Buffer™?

It certainly is. An overdose of Alkaline Buffer™ can result in a sudden and stressful shift in pH and KH.  If pH or KH of the water is still incorrect despite repeated additions of a buffer like Alkaline Buffer™, it is likely that there is a high concentration of acids or buffers in the aquarium that are resisting the change in pH.