crispypb840
Active Member
I was wondering what I should use (Organic) to raise my pH when mixing my feed. I use General Organics. Right now I have been using a powder I got at wall mart in the pool section. Is there anything wrong w/ the powder?
Organic pH up?
- Thread starter crispypb840
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oregongrowpros
Well-Known Member
baking soda increases ph, but use it in very small doses
SpicySativa
Well-Known Member
I personally would avoid adding anything solely for the purpose of adjusting pH, especially sodium bicarbonate (baking soda). I don't hesitate to pour on things like fish hydrolysate, even though the pH may be down around 4-4.5. A good living soil will have no problem buffering this, and you avoid adding unnecessary extra things like sodium.
A little silica (potassium silicate) is never a bad idea, but don't get caught up in trying to add the perfect amount for the perfect pH. The second the solution hits your soil, it takes on the pH of the soil. Adjusting the pH of your solution has VERY little affect on actual soil pH. In other words, it would take many repetitive feedings at low pH to cause any real shift in your soil.
What WILL start affecting your soil's pH (usually in a bad way) is repeatedly adding things like potassium bicarbonate or sodium bicarbonate in an effort to find that "perfect" number.
A little silica (potassium silicate) is never a bad idea, but don't get caught up in trying to add the perfect amount for the perfect pH. The second the solution hits your soil, it takes on the pH of the soil. Adjusting the pH of your solution has VERY little affect on actual soil pH. In other words, it would take many repetitive feedings at low pH to cause any real shift in your soil.
What WILL start affecting your soil's pH (usually in a bad way) is repeatedly adding things like potassium bicarbonate or sodium bicarbonate in an effort to find that "perfect" number.
crispypb840
Active Member
I only need it when I feed using r/o or rain water. I have well water where I live witch is fine but I noticed ppm's are around 140 and pH around 7.5 so It actually works where I don't need pH up when mixing nutes but ppm's are higher. Do you think it is better to mix feed w/ well water or rain water and add pH up?
SpicySativa
Well-Known Member
If your asking ME what I think would be better, I would say rain water WITHOUT adjusting pH.
The reason you "need" it when using rain or RO water is because the water has little to no buffering ability. In other words it has very little resistance to pH change, so it easily takes on the low pH of your nutrients. The well water has more buffering ability, so it resists pH change a little more.
Either way, healthy soil is much more strongly buffered than nutrient solution. When you pour it on, the solution takes on the pH of the soil, while the soil pH remains mostly unchanged.
I can honestly tell you from years of experience: STOP WORRYING ABOUT THE pH OF YOUR WATER OR NUTRIENT SOLUTION!!! Focus on maintaining healthy, living soil, through the liberal use of compost, and your soil pH will mostly take care of itself.
The reason you "need" it when using rain or RO water is because the water has little to no buffering ability. In other words it has very little resistance to pH change, so it easily takes on the low pH of your nutrients. The well water has more buffering ability, so it resists pH change a little more.
Either way, healthy soil is much more strongly buffered than nutrient solution. When you pour it on, the solution takes on the pH of the soil, while the soil pH remains mostly unchanged.
I can honestly tell you from years of experience: STOP WORRYING ABOUT THE pH OF YOUR WATER OR NUTRIENT SOLUTION!!! Focus on maintaining healthy, living soil, through the liberal use of compost, and your soil pH will mostly take care of itself.
foreverflyhi
Well-Known Member
Ph does not matter in water scedule for organics.
crispypb840
Active Member
Thanks for the insight. I do understand and will take your advise. So rainwater will more easily adjust to the soil's natural pH. Makes sense.
Jack Harer
Well-Known Member
FINALLY someone else who understands what a buffer is!! (J/K Spicy, I've always known you know your shit!!) So many folks haven't a clue about pH, and buffering vs temporary changes.
Crispy, your rain water pH should be around 4 or so, due to the ever present sulfur dioxides and carbon dioxides in the atmosphere. That's why I don't use rain water any more. It's no better than my tap water. My tap is actually better in my opinion due to the presence of dissolved minerals.
Jack Harer
Well-Known Member
Nullis, guess I should have qualified that with "anywhere east of the Mississippi, it's ALL acid rain to one extent or the other" Here in Tennessee/N. Ga it's right at 4. NY, DC and the Appalachians it's even more acidic.
SpicySativa
Well-Known Member
Indeed. "Normal" rainwater will have a pH around 6 due to the carbonic acid that forms from the reaction between water and carbon dioxide. Despite a pH that is a little skewed from neutral (7) the rainwater has practically zero buffering ability. The very slightest little bit of acid or base added to it will change the pH in a big way. Put it in your soil, it will very quickly take on your soil's pH.
My rainwater is 7-7.5, according to my WalMart device, which measures light, moisture, and ph. I use it to water and to make llama tea (from composted llama poo from my llamas). Llama poo is supposed to be on the alkaline side. (This is basically my first grow). When test soil in pots, registers the same - 7.5. My plants are growing fine, indoors, but 8 weeks and no signs of preflowering, or sex. Should I put them on 12/12, or do you think the ph should be lower, amd how lower organically. I tried to grow once before, but killed most of the plants with vinegar. Comments, adv
SpicySativa
Well-Known Member
That device is for measuring SOIL pH, not water. And the accuracy of those cheapy meters is questionable at best. If you want a cheap and accurate pH check, get some litmus paper or some pH test drops from the pool store or hydro shop.
That said, I would not worry about or attempt to adjust the pH of your rainwater.
That said, I would not worry about or attempt to adjust the pH of your rainwater.
crispypb840
Active Member
My rain water is exactly 6.6 and around 10 ppm. My run off is 6.7 and 700ppm.
crispypb840
Active Member
I'm glad I learned about this. I hate adding pH adjuster. What exactly is in the soil that buffer's it? I'm using Ocean Forest. I know that adding lime helps but more is there to it?
SpicySativa
Well-Known Member
I suggest reading up on Cation Exchange Capacity (CEC) and base saturation (percent of cation exchange sites occupied by "basic" elements like calcium and magnesium. Therein lies the answer to your question.
Here's a good place to start:
http://soils.tfrec.wsu.edu/webnutritiongood/soilprops/04CEC.htm
Here's a good place to start:
http://soils.tfrec.wsu.edu/webnutritiongood/soilprops/04CEC.htm
Jack Harer
Well-Known Member
What ever FF uses to adjust the pH of their soil. It could be garden lime, but in this case I believe they use either dolomite or oyster shell. Either way, it's calcium carbonate that acts as the buffer. Don't sweat pH in soil. Again, don't sweat pH in soil. pH in soil is a non-issue.
Forget thepH of whats going in or coming out. The soil will adjust that.
crispypb840
Active Member
Ok. Thanks. It's become clear to me.
