dvc_r
Member
I'm going away for a few days so I am doing water changes before I leave. I used a new API test kit and found my readings were not too bad. For some reason I decided to test them again using my old, almost empty bottles. The results were about 10 ppm difference!
Before everyone tells me about shaking, hitting, banging, throwing, and gently placing bottle on top of a nuclear reactor 2 seconds before detonating... I assure you I did "most of that! Also I'm well aware of the expiration date (in this case the bottles lot numbers reflect 05-08 and 08-08), so I do not think that's the reason.
The only other thing I can think of is that the crystals in the older bottle may have slowly settled each time I used it and over time creates a higher reading. Now I'm not sure what to believe!
Here is a picture of the results of each test (side by side) of all three tanks:
Before everyone tells me about shaking, hitting, banging, throwing, and gently placing bottle on top of a nuclear reactor 2 seconds before detonating... I assure you I did "most of that! Also I'm well aware of the expiration date (in this case the bottles lot numbers reflect 05-08 and 08-08), so I do not think that's the reason.
The only other thing I can think of is that the crystals in the older bottle may have slowly settled each time I used it and over time creates a higher reading. Now I'm not sure what to believe!
Here is a picture of the results of each test (side by side) of all three tanks:
