Smokedogg76
Well-Known Member
I always hear of different ways to PH your nutrients. What cha got. Basically, what brand do you use and what is your technique when adding it to your resi?
How do you PH?
- Thread starter Smokedogg76
- Start date
BluBerry
Well-Known Member
was using vinegar to lower ph but it caused buildup in the res and it did not keep my ph stable at all for any length of time. I now am using Advanced Nutrients pH down that i put into a visine bottle and just use a few drops every couple days or so and it works great. very potent so a bottle will go a long way
Bud King USA
Member
Hello friend. Hope this information, which I wrote several years ago for another article, helps you with your pH dilema.
The pH is a measure of the acidity or the alkalinity of the solution. Normally the pH ranges from 0 to 14. A low pH (lower than 7) means that a solution is acidic. Pure water has a pH of around 7 which is neutral. Higher than 7 is called alkaline. Acidic solutions can be neutralised with alkaline solutions and vice versa. Too acidic is fatal for any plant and so is too alkaline. One of the causes is that the nutrients change into a, for the plant, unabsorbable form when the pH becomes too high or low.
The pH of the nutrient solution should be checked regularly with a pH meter.
Once you have added your nutrient to your water, measured and set your required EC, let the nutrient solution sit for a few hours, then adjust your pH.
Hope this helps.
The pH is a measure of the acidity or the alkalinity of the solution. Normally the pH ranges from 0 to 14. A low pH (lower than 7) means that a solution is acidic. Pure water has a pH of around 7 which is neutral. Higher than 7 is called alkaline. Acidic solutions can be neutralised with alkaline solutions and vice versa. Too acidic is fatal for any plant and so is too alkaline. One of the causes is that the nutrients change into a, for the plant, unabsorbable form when the pH becomes too high or low.
The pH of the nutrient solution should be checked regularly with a pH meter.
- pH too high: lower it with
- Nitric acid (during the growth period)
- Phosphoric acid (during the flowering period)
- pH too low: increase it with
- an alkaline solution (during the whole period)
Once you have added your nutrient to your water, measured and set your required EC, let the nutrient solution sit for a few hours, then adjust your pH.
Hope this helps.
Smokedogg76
Well-Known Member
bump.......
Mike Young
Well-Known Member
Yeah, I learned my lesson with vingar too. Not worth it. I bought a bottle of GH PH down. Works great. If I need to raise the ph, I go with pro tekt silica which also strengthens stems.
bowlfullofbliss
Well-Known Member
General Hydroponics. The orange stuff. It's always treated me well. Pice is right. Make sure you invest in a good quality PH/Temp pen, and keep it dialed in with PH buffer solution. Too many guys forget to clean it with soap and water, and make sure they keep it spot on with the solution. I personally use a 7.0 solution to keep it right.
As for the silica referred above, I use that in every res I have. It's a good ph up, if you just need to go up by a cunt hair, but I just keep around a bottle of GH up for any errors. Using the silica makes your plants have wood at their bases in a matter of a couple of weeks. I mean serious tree bark.
Stoobie
Well-Known Member
What is General Hydroponics pH Up and Down? What's in that bottle? My quart-sized bottles just say "acid" and "base."
To answer the original questions:
I use GH pH up and down. It's cheap, performs consistently, and seems to last a long time.
I already know how much pH down I'll need, so I usually add it to my water when I pour it. If you're asking how I physically apply it, I use a 1/4 teaspoon. I only need about 3 drops per gallon usually.
To answer the original questions:
I use GH pH up and down. It's cheap, performs consistently, and seems to last a long time.
I already know how much pH down I'll need, so I usually add it to my water when I pour it. If you're asking how I physically apply it, I use a 1/4 teaspoon. I only need about 3 drops per gallon usually.
I use sulfuric acid. Bought 6 quarts at an auto parts store for $15, which is pretty much a lifetime supply for me. I'm too lazy to dilute it, so I keep a small glass jar with glass eye dropper on the shelf. My well water starts at 8-8.5 PH, takes probably 7 ml or so to bring 5 gallons to a PH of 6. That's just a guess though, as I just use two dropper fulls and haven't measured how much that actually is.
TaoWolf
Active Member
Same at my location. 8.5'ish pH out of the tap.
I use two tsp (~10mL) of phosphoric acid per five gallons of water to lower it to ~6. A local chemistry company makes and bottles the pH Down for the local hydro store I go to - it's cheap. About $7 for a bottle that will last me half a year.
Smokedogg76
Well-Known Member
Does anyone worry about nute burn?
Smokedogg76
Well-Known Member
When you add ph down, do any of you guys worry about nute burn? I don't want to kill off those beneficial microbes.
nothingtodeclare
Active Member
here some info for those who dont know i use growth technology jus ph down do not need ph up just add plain water here's some info for those trying how to find out how to ph
Optimum pH for nutrient solutions
For nutrients to remain dissolved and, therefore, available for uptake by roots, it is critical to maintain the pH between 5.0 and 6.0 with an absolute maximum of 6.5. When the pH of the nutrient solution is above 7.0, calcium, sulfate (and trace elements of copper, iron, manganese and zinc) can precipitate and become unavailable to the roots, causing plumbing blockages. High pH values, or those above 6.0, are to be avoided more than low values of 4.5 to 5.0. The effect of low pH upon the stability of nutrients is relatively insignificant.
The precise pH at which precipitation of macro-nutrients starts is determined by the combined concentrations of calcium and sulfate. Except for fertilizers low in calcium and sulfate this problem commonly occurs at pH 6.5 where the net* EC is 2.5 mS, or pH 7.0 for 1.5 mS solutions. Hence, to avoid precipitation, higher nutrient concentrations generally must be held at lower pH values. *Assume make-up water has nil EC.
In spite of this precipitation problem, some references advocate pH values well above 6.5 for some plant varieties, conditions that risk depleted concentrations of the above mentioned elements.
Figure one: Simplified illustration of how nutrient uptake effects pH of the nutrient solution
pH recommendation of 6.2 to 6.3?
Although 6.2 to 6.3 is a popular pH recommendation, which has no scientific basis. It appears to have gained mythological status from the early days of hydroponics when the only cheap means of measuring pH was the common ‘bromothymol blue’ pH indicator used for testing fish tank water. Interestingly, the lowest pH value able to be determined by that indicator is about 6.2. Hence, this value has unfortunately become an entrenched recommendation in some sections of the hydroponic industry.
Adjusting nutrient pH
The working nutrient pH should be checked at the following times:
Figure two: pH indicators are useful for determining how much acid needs to be added to the nutrient reservoir.
How to minimize pH fluctuation
Step 1. Measure the pH: Use either a liquid pH indicator or an electronic pH meter (see sections below). Before measuring the pH, ensure that the nutrient is well stirred and that the sampling container is clean.
Step 2. Choosing a target pH: Note that it is inconvenient and unnecessary to hold pH at a single point value. Therefore, choose a target pH that minimizes the amount of pH maintenance:
Step 3. Adjusting the pH: Add a small amount of pH down or up product*. Then stir well and check pH. Repeat this process until the target pH is achieved.
*Important: Pre-dilute the dose into one quart (or at least 100 fold) of water before adding to nutrient, then rapidly stir the nutrient as you add this mixture. Failure to do this may cause permanent precipitation of essential nutrients. Also, if accidental overdosing to above 6.5 occurs, reduce the pH back to below 6.0 as quickly as possible using pH down.
Figure three: This is the color range produced by a wide range pH indicator within the optimum pH range 5.0 to 6.5. Note the ease with which pH change can be detected.
Handy hints for adjusting nutrient pH
1. Add “high pH” (alkaline) additives before adding nutrient: Most additives will affect nutrient pH at least slightly. The best technique to adopt with those that elevate pH significantly is to add them to the water and adjust the pH down to 6.0 prior to adding the nutrient.
The less preferred but simplest alternative is to pre-dilute the additive in a separate volume of raw water. Then once this solution is added to the nutrient solution, quickly lower the pH to below 6.5. Note that a white cloudy precipitate (calcium sulfate) may form when the pre diluted additive initially merges with the nutrient solution. However, because the initial particle size of the precipitate is small, it will usually re-dissolve if the pH is immediately re-adjusted.
2. Do not pre-adjust pH of raw water: Note that the pH values being discussed here are the values of the working nutrient solution, not your make-up water. Unless your make-up water has a high alkalinity, do not bother attempting to adjust its pH prior to the nutrient being added. If you attempt this procedure you will typically get wild pH swings either side of the pH target without ever landing on the target value.
3. Estimating the volume of acid (especially for larger systems):
pH indicators are undoubtedly the simplest and most reliable method of measuring nutrient pH. Although they will not distinguish between, for example, a pH of 5.2 and 5.3, wide range indicators with good color resolution can be:
pH indicators work on the principle that the color produced by the particular dye used in the indicator formulation is dependant on the pH of the solution (figure three).
Experience shows if you are aiming to adjust pH to 5.5 (orange) then an accuracy of +/- 0.2 is achievable. Because of their fundamental accuracy, reliability and easy of use, wide range pH indicators are the preferred method for measurement of pH in nutrient solutions. Note that pool and aquarium pH indicators are usually not suitable because unlike broad range indicators, they do not operate below pH 6.0.
Figure four: Thoroughly stir nutrient reservoir before sampling. Then leave the electrode in the sample for a few minutes before switching the meter on and taking the measurement. Do not immerse the electrode deeper than ~1 inch.
Taking pH readings
Step 1. Before measuring the pH ensure that the nutrient is well stirred, especially after pH up or down products are used. This is one of the most common mistakes made when testing pH (or conductivity). Also, ensure that the sampling container is clean.
Step 2. Using the sampling vial, remove a small sample of nutrient from the nutrient reservoir, add a drop of the indicator, mix, and then compare the final solution color with those on the colored reference chart (figure three).
Step 3. If the pH is not between 5.0 and 6.5, adjust it immediately.
Measuring pH with pH meters
pH meters employing a glass electrode are useful for precise pH measurement in nutrient solutions but require frequent calibration, proper storage and handling to ensure accuracy and reliability. The principle on which such meters operate is based on the fact that when glass of a certain composition separates two aqueous solutions having different hydrogen ion concentrations, a voltage is developed between the two faces of the glass. The electronic meter is simply a very sensitive voltmeter which measures that voltage but is calibrated in terms of pH units instead of volts.
Obtaining pH readings
Step 1. Make sure the meter is calibrated.
Step 2. Remove a ‘representative’ sample from the nutrient reservoir (figure four):
Step 4. If the pH is not between 5.0 and 6.5, adjust it immediately.
Step 5. When complete, rinse the electrode with distilled water. Store the electrode in a proper storage solution when not in use.
Optimum pH for nutrient solutions
For nutrients to remain dissolved and, therefore, available for uptake by roots, it is critical to maintain the pH between 5.0 and 6.0 with an absolute maximum of 6.5. When the pH of the nutrient solution is above 7.0, calcium, sulfate (and trace elements of copper, iron, manganese and zinc) can precipitate and become unavailable to the roots, causing plumbing blockages. High pH values, or those above 6.0, are to be avoided more than low values of 4.5 to 5.0. The effect of low pH upon the stability of nutrients is relatively insignificant.
The precise pH at which precipitation of macro-nutrients starts is determined by the combined concentrations of calcium and sulfate. Except for fertilizers low in calcium and sulfate this problem commonly occurs at pH 6.5 where the net* EC is 2.5 mS, or pH 7.0 for 1.5 mS solutions. Hence, to avoid precipitation, higher nutrient concentrations generally must be held at lower pH values. *Assume make-up water has nil EC.
In spite of this precipitation problem, some references advocate pH values well above 6.5 for some plant varieties, conditions that risk depleted concentrations of the above mentioned elements.
pH recommendation of 6.2 to 6.3?
Although 6.2 to 6.3 is a popular pH recommendation, which has no scientific basis. It appears to have gained mythological status from the early days of hydroponics when the only cheap means of measuring pH was the common ‘bromothymol blue’ pH indicator used for testing fish tank water. Interestingly, the lowest pH value able to be determined by that indicator is about 6.2. Hence, this value has unfortunately become an entrenched recommendation in some sections of the hydroponic industry.
Adjusting nutrient pH
The working nutrient pH should be checked at the following times:
- When working nutrient solutions are first made.
- After the addition of top-up water or additives, especially if they are highly alkaline.
- In re-circulating systems, pH should be checked on a daily basis because the uptake of water and nutrients causes pH to change (figure one).
How to minimize pH fluctuation
- Use a nutrient brand that is highly pH buffered, particularly when using highly alkaline water.
- Supply at least two gallons of nutrient for each large plant. Failure to do this will magnify pH (and EC) fluctuations, especially during hot and dry weather where water uptake and evaporation are excessive. Note, to avoid excess water uptake and evaporation; keep air temperature below 86oF and relative humidity above 50 per cent.
Step 1. Measure the pH: Use either a liquid pH indicator or an electronic pH meter (see sections below). Before measuring the pH, ensure that the nutrient is well stirred and that the sampling container is clean.
Step 2. Choosing a target pH: Note that it is inconvenient and unnecessary to hold pH at a single point value. Therefore, choose a target pH that minimizes the amount of pH maintenance:
Step 3. Adjusting the pH: Add a small amount of pH down or up product*. Then stir well and check pH. Repeat this process until the target pH is achieved.
*Important: Pre-dilute the dose into one quart (or at least 100 fold) of water before adding to nutrient, then rapidly stir the nutrient as you add this mixture. Failure to do this may cause permanent precipitation of essential nutrients. Also, if accidental overdosing to above 6.5 occurs, reduce the pH back to below 6.0 as quickly as possible using pH down.
Handy hints for adjusting nutrient pH
1. Add “high pH” (alkaline) additives before adding nutrient: Most additives will affect nutrient pH at least slightly. The best technique to adopt with those that elevate pH significantly is to add them to the water and adjust the pH down to 6.0 prior to adding the nutrient.
The less preferred but simplest alternative is to pre-dilute the additive in a separate volume of raw water. Then once this solution is added to the nutrient solution, quickly lower the pH to below 6.5. Note that a white cloudy precipitate (calcium sulfate) may form when the pre diluted additive initially merges with the nutrient solution. However, because the initial particle size of the precipitate is small, it will usually re-dissolve if the pH is immediately re-adjusted.
2. Do not pre-adjust pH of raw water: Note that the pH values being discussed here are the values of the working nutrient solution, not your make-up water. Unless your make-up water has a high alkalinity, do not bother attempting to adjust its pH prior to the nutrient being added. If you attempt this procedure you will typically get wild pH swings either side of the pH target without ever landing on the target value.
3. Estimating the volume of acid (especially for larger systems):
Step 1. Take a one quart sub-sample (or known volume) of working nutrient.
Step 2. Add a few drops of pH indicator (figure two ‘a’
.
Step 3. While stirring this solution, measure the volume of acid required to turn this solution yellow – figure two ‘b’ (Yellow indicates a pH of 6.0 with most broad range liquid indicators).
Step 4. Multiply the volume of acid* by the volume of nutrient in your reservoir. That calculation will give you the volume of acid required to adjust the entire volume down to pH 6.0, for example.
Measuring pH with ‘indicators’Step 2. Add a few drops of pH indicator (figure two ‘a’
.Step 3. While stirring this solution, measure the volume of acid required to turn this solution yellow – figure two ‘b’ (Yellow indicates a pH of 6.0 with most broad range liquid indicators).
Step 4. Multiply the volume of acid* by the volume of nutrient in your reservoir. That calculation will give you the volume of acid required to adjust the entire volume down to pH 6.0, for example.
pH indicators are undoubtedly the simplest and most reliable method of measuring nutrient pH. Although they will not distinguish between, for example, a pH of 5.2 and 5.3, wide range indicators with good color resolution can be:
- fast and user friendly
- extremely accurate and reliable
- economical
pH indicators work on the principle that the color produced by the particular dye used in the indicator formulation is dependant on the pH of the solution (figure three).
Experience shows if you are aiming to adjust pH to 5.5 (orange) then an accuracy of +/- 0.2 is achievable. Because of their fundamental accuracy, reliability and easy of use, wide range pH indicators are the preferred method for measurement of pH in nutrient solutions. Note that pool and aquarium pH indicators are usually not suitable because unlike broad range indicators, they do not operate below pH 6.0.
Taking pH readings
Step 1. Before measuring the pH ensure that the nutrient is well stirred, especially after pH up or down products are used. This is one of the most common mistakes made when testing pH (or conductivity). Also, ensure that the sampling container is clean.
Step 2. Using the sampling vial, remove a small sample of nutrient from the nutrient reservoir, add a drop of the indicator, mix, and then compare the final solution color with those on the colored reference chart (figure three).
Step 3. If the pH is not between 5.0 and 6.5, adjust it immediately.
Measuring pH with pH meters
pH meters employing a glass electrode are useful for precise pH measurement in nutrient solutions but require frequent calibration, proper storage and handling to ensure accuracy and reliability. The principle on which such meters operate is based on the fact that when glass of a certain composition separates two aqueous solutions having different hydrogen ion concentrations, a voltage is developed between the two faces of the glass. The electronic meter is simply a very sensitive voltmeter which measures that voltage but is calibrated in terms of pH units instead of volts.
Obtaining pH readings
Step 1. Make sure the meter is calibrated.
Step 2. Remove a ‘representative’ sample from the nutrient reservoir (figure four):
- Stir the nutrient thoroughly prior to sampling.
- Ensure the sampling container is clean.
Step 4. If the pH is not between 5.0 and 6.5, adjust it immediately.
Step 5. When complete, rinse the electrode with distilled water. Store the electrode in a proper storage solution when not in use.
Bonzi Lighthouse
Well-Known Member
Eyedropper, the best $$$ I've ever spent, 10 drops of GH Ph down/gal and I'm right at 5.5 - 5.8
BeaverHuntr
Well-Known Member
GH PH Up and PH Down here.