Bill C
New Member
When my plants are in Bloom, the pH is fairly stable. I have to make a slight adjustment 2 days after a nute change, but it stays within the 5.2 - 5.9 range for hydro the rest of the week.
However, during the few weeks I veg them, the pH tends to rise quite a bit. Ideally, I would prefer to use nitric acid for pH control as I figure the extra N won't hurt during the grow period. Unfortunately, since nitric acid is an ingredient used by some wacos to blow things up, I don't really want to ask for it.
I've looked at pH down products which tend to be phosphoric acid. While the extra P may be good in bloom, do I really want to give them extra during grow?
I heard someone mention battery acid one time on a forum long since forgotten (it might have been here!), so I looked a little closer. Battery acid is simply 30% sulphuric acid (h2so4). So as the reaction takes place for pH control, sulphur is released into the nute solution.
I've seen the plant abuse charts that mention sulphur toxicity, but I've never seen it myself. According to Spectrum Analytic, "Sulfur toxicity for practical purposes should be considered as non-existent. Excessive applications most often result in a depression of soil pH and an increase of the problems that occur with the pH decrease. In fact, sulfur uptake is reduced as the pH of the soil decreases."
In a study conducted by Richard M. Cooper & Jane S. Williams (I know... who??? nonetheless, a couple of people with more letters after their names than I have), not only is sulphur well suited as a fungicide as a foliar spray (this has been known for thousands of years), they found that plants with a higher sulphur content were less likely to become infested to begin with. They talked specifically about PM.
I'm in my second year of using it, have not had PM since (knock on wood!), and the girls seem to be very happy. Mileage will vary, but in my setup, I've found that 0.5 mL per gallon will drop the pH by a full point, so use slowly and let it adjust for at least 5 minutes, if not more. It seems to drop slow and steady for a while. It's available at any auto parts store for $4 a quart.
So, it's on the table. Am I completely insane, or have others tried it and what results were obtained? I have no complaints after over a year, although I have to admit I held my breath the first week I started using it. Part of my brain said it'd be fine, but the other part kept yelling, "IT'S BATTERY ACID!" ha!
However, during the few weeks I veg them, the pH tends to rise quite a bit. Ideally, I would prefer to use nitric acid for pH control as I figure the extra N won't hurt during the grow period. Unfortunately, since nitric acid is an ingredient used by some wacos to blow things up, I don't really want to ask for it.
I've looked at pH down products which tend to be phosphoric acid. While the extra P may be good in bloom, do I really want to give them extra during grow?
I heard someone mention battery acid one time on a forum long since forgotten (it might have been here!), so I looked a little closer. Battery acid is simply 30% sulphuric acid (h2so4). So as the reaction takes place for pH control, sulphur is released into the nute solution.
I've seen the plant abuse charts that mention sulphur toxicity, but I've never seen it myself. According to Spectrum Analytic, "Sulfur toxicity for practical purposes should be considered as non-existent. Excessive applications most often result in a depression of soil pH and an increase of the problems that occur with the pH decrease. In fact, sulfur uptake is reduced as the pH of the soil decreases."
In a study conducted by Richard M. Cooper & Jane S. Williams (I know... who??? nonetheless, a couple of people with more letters after their names than I have), not only is sulphur well suited as a fungicide as a foliar spray (this has been known for thousands of years), they found that plants with a higher sulphur content were less likely to become infested to begin with. They talked specifically about PM.
I'm in my second year of using it, have not had PM since (knock on wood!), and the girls seem to be very happy. Mileage will vary, but in my setup, I've found that 0.5 mL per gallon will drop the pH by a full point, so use slowly and let it adjust for at least 5 minutes, if not more. It seems to drop slow and steady for a while. It's available at any auto parts store for $4 a quart.
So, it's on the table. Am I completely insane, or have others tried it and what results were obtained? I have no complaints after over a year, although I have to admit I held my breath the first week I started using it. Part of my brain said it'd be fine, but the other part kept yelling, "IT'S BATTERY ACID!" ha!
