Kalk Overdose

[robf]

EMBARRASSED!!!! I'm totally humiliated in myself but feel I need to write this to hopefully prevent another person from making the same mistake as I have. Fortunately no livestock has been lost and you all are largely to thank for that. It appears that no kalk was overdosed but in fact my pH meter went out of calibration. I re calibrated both my in tank probe and my Hanna Checker hand held model. Turns out pH was not high but low at 7.55. My low dKH numbers should have been a tell. Fortunately I didn't do anything to drive it lower yet. I could have killed a lot of critters! I suppose there is a possibility that both meters are incorrectly calibrated to this new level but I did use calibration solution for both meters. The one thing I couldn't quite get exact was the calibration temp. I believe that 77F is the temp the calibration solution is designed for. My tank is running at about 80F and the prob is connected to the sump an so the solution was resting in an area where the solution warmed to tank temp. Conversely, the ambient temp for my hand held was 72F. Regardless I feel both meters are close enough for my purposes. Digital Aquatics recommends re-calibrating every 2 months and more frequently than that as the probe ages. They recomend replacing the probe every 12 months. My wife, a chemist tells me they re-calibrate their lab probes often 2x each day. She tells me pH probes are notoriously subject to drifting errors. So, I recommend re-calibrating before you try anything related to dosing or changes. I plan on buying another probe to have one handy for the event this happens again. From here on out I am re-calibrating every 2-3 weeks. Hope this lesson helps someone else to avoid this mistake than this thread is worth it.

 

[lpslover]

Glad things worked out. I wouldn't be too embarassed. We all have stories to tell of when we were just starting reefing and did something stupid or insane. This hobby takes a lot of research and a lot of experience and that only comes with time. Be glad your tank survived and think about how much you learned from the experience.

Also it could have been that the pH spike itself caused your probe to malfunction and need recalibration. This is why as has been mentioned, most experienced reefers take pH readings with a grain of salt. pH can be affected by a half dozen factors, so while it is useful, dosing and management decisions should not be made on it without taking all other parameters into account.