Question about dosing and PH

GhoSt3366 · May 19, 2015

Hello all,

I started to dose vinegar a little over a week ago. At the time my ph would stay around 8.1 to 8.2. When I starting doing (started at 5ml in a 120 display) I noticed the mentioned ph drop right away and then it would rebound which i expected based on research. After 5 days I noticed that the ph was staying around 8.05 and would still drop when I dosed and come back to around 8.05, but never back up to the usual 8.1-8.2 I was at before dosing. I stopped doing 2 days ago, because I didn't know if this is normal or not. I do have ph buffer if needed, but didn't want to start adding this also unless needed. Can someone let me know if this is normal, I did not find anything about this through my reading.

sal. 1.025
ph 8.05
nitrate 60
KH 8.5
cal 400

Thank you

Randy Holmes-Farley · May 19, 2015

It is normal when dosing organic carbon for the pH to run a bit lower since carbon dioxide is produced as the organic is metabolized. The overall pH lowering is about the same whether using vinegar, vodka, or something else, but when using vinegar about half of the drop is instantaneous, and the rest over time, while with vodka it is spread more over time.

In your case, I wouldn't stop dosing just because of the pH drop you observed.

GhoSt3366 · May 19, 2015

Hi Randy,

Thank you for the reply, and suggestion. I will start dosing again, but with one a follow up question. When would you recommend being concerned about the ph drop? I took a sample in to my LFS to confirm my reading and they were getting 7.8-7.9 and told me to act to correct this situation. What number would you be concerned at and when you got to that number would you stop dosing or add buffer or something else to try to raise it?

Thank you again