Is there anyway that 4dKH drop checker solution can go bad. I have had this bottle since last summer it came with my red sea drop checker. I moved my fish tank a few weeks ago and left the drop checker at my parents for a few weeks and ever since i have moved back it seems that the solution is off it is telling me i have no co2 in my tank even when the fish show stress from me turning up the co2. I am not sure if it had anything to do with my plants slowing down growth too or that could just be from them becoming accustomed to the new water parameters? I know co2 is getting into the tank bc i have the line hooked up to a power head and there is mist going everywhere. Anyone have any info for me?