11-06-2008, 10:25 AM
Join Date: Jan 2007
iTrader Positive Rating: 100%
| | Re: Calibrate your drop checker, CO2 is bad for fish!
I suspect it would be prudent for you to double check the calibration of your pH meter and the dKH of your drop checker's solution before you go off dismissing the work of numerous others on the subject.
Personally, I know my 4dKH solution is spot-on as I made it myself from baking soda whose moisture content was known and corrected for and water that is of the highest purity, right from the tap of a Milli-Q Gradient A10 TOC polishing unit fed by an Elix water system (top shelf stuff, even by lab standards). When my drop checker is green, I'm in the 15PPM-30PPM CO2 window. My fish are fine.
pH controllers are only as good as their probes. If probes are neglected, CO2 delivery accuracy will suffer. If your probe gets gunked up at a pH above your set point, your CO2 tank will remain "on" until the pH drops to a certain point - which may be never, as far as your probe is concerned. You should also regularly calibrate the probe using standard buffers bracketing the range of pH values you anticipate the probe seeing. In addition to accuracy, you need to pay attention to the response time of the probe.
pH controllers are not "set it and forget it" devices.