? for all you chemistry buffs

[gt8448a]

Hi everyone. I'm trying to figure out how my pH could have dropped over .3 units since this past Saturday. The only 2 explanations I can come up with at this point are: I added 2.5 ml Ca supplement on Sunday, or the pH test tube was swapped with the NO3 test tube. Other than that, nothing else has changed. Does anyone have any ideas what might have happened? Thanks for the advice.

Harrell

 

[AnotherGoldenTeapot]

pH can change by much more than you expect during the course of a single day.

For example, try measuring the pH just before the lights go on in the morning and then again just before they go off in the evening. It would not be that unusual to see a pH change as big as you are pondering.

Due to this, it's perhaps best to always measure pH at the same time of the day so that you can measure trends over time.

Adding 2.5ml of anything is not going to impact much on the pH of your tnak unless you're running a truly tiny tank.

If you really do have a problem then I'd look at your alkalinity level first.

 

[gt8448a]

Thanks for the advice, Teapot. I had been checking the pH only 1x a week, sometimes 2x, but now that I've started keeping shrooms and other things, maybe I should begin a daily monitoring. And yes, my tank is rather small (10g), since I'm relatively new to the hobby. The change in pH has never been this drastic, however.

Thanks again for the advice. ---Harrell

 

[tetra]

Don't forget about the accuracy of the instrument and buffer solutions that is used to calibrate it. A point 0.3 fluctuation is not so bad.