You're never going to get an accurate test without proper machines and apparatus at the end of the day
I mean accurate as in matching the chart.
The drop checkers are really just and indication that something is a miss.
It's worrying that you have read reports on some failing to read high c02 when livestock were gasping.
As mentioned, In marine setups where buffers are part of the habitat and where alkalinity is closely monitored changes in ph do warrant close inspection with particular attention to co2
Is the drop checker telling us anymore than this approach?
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