Zandor (or anyone else knowledgable about such matters),

This novice can't seem to keep his nutrient solution at a constant pH. I'll set the pH to about 5.3, but within 7 or 8 hours, it will rise to over 7 (around 7.1 or so). I correct the pH by adding granulated citric acid, which takes it back down to the low 5's, but again, in only a few hours, it's risen well above the applicable range (5.2-5.9). I know pH usually drifts up (and this is even beneficial to the plant as it can absorb a wider range of nutrients as the pH changes), but I was always under the impression that normal upward pH drift is much slower - on the order of several days or more, not several hours as I have been experiencing.

My reservoir is small - only about 7 liters, and I have an airstone to keep things aerated and bubbling, and I change the entire solution every week. I also use only organic nutes (Advanced Nutrients Iguana Juice, Enggy's Humic/Fulvic Acid, etc.). I've already lost my very first plant (sob), but I have a garden of new seedlings that are just beginning to open up. Any thoughts or help you can give would be MOST appreciated.
anchman Reviewed by anchman on . Rising pH Zandor (or anyone else knowledgable about such matters), This novice can't seem to keep his nutrient solution at a constant pH. I'll set the pH to about 5.3, but within 7 or 8 hours, it will rise to over 7 (around 7.1 or so). I correct the pH by adding granulated citric acid, which takes it back down to the low 5's, but again, in only a few hours, it's risen well above the applicable range (5.2-5.9). I know pH usually drifts up (and this is even beneficial to the plant as it can absorb a Rating: 5