You might want to test something else with your test kit just to make sure it isn't the test kit that is faulty. I once really crashed a hydroponic system when my pH meter quit working. I kept adding the pH down and the meter kept saying 7.
Finally I pulled out the old litmus strips and checked the nutrient was down around 4 by that time.
Right now I'm using a Mars liquid test kit. I get different readings in the hydroponic system so I'm fairly certain that the kit is okay. This ph down has no smell whatsoever. If anybody has a bottle of Technaflora PH down in their possesion, maybe you can tell me if there is a smell to it. Thx
End of the mystery....As it turns out, the folks over at the hydroponics store stand behind what they sell and gave me a new bottle of ph down (same brand). Just as I thought this new bottle tested the way it is supposed to. Got a bad bottle after all somehow......Thanks David!!!!