What is your runoff pH?
FYI: RO water has no pH and growers should not attempt to adjust it. A pH exists in water if and only if ions are present. RO contains no ions and therefore has no pH. RO will take on the pH of the medium intro which it is introduced.
Let’s get some more info as well:
A support ticket will help us help you. Can you please fill out a support ticket? Please include what type of water you are using (RO, distilled, tap.)
COPY/PASTE the below list into your forum post.
Answer these simple questions the best you can.
If you do not know, or do not use something; Just say so; Or post
NA (non-applicable)
• What strain, Seed bank, or bag seed
• Method: Soil w/salt, Organic soil, Hydroponics, Aquaponics, KNF
Soil brand and type
• Vessels: Pots, Grow beds, Buckets, Troths
• Runoff pH
• Runoff PPM/TDS or EC
• Indoor or Outdoor
• Light system and wattage
• Temps; Day, Night
• Humidity; Day, Night
• Ventilation system; Yes, No, Size
• AC, Humidifier, De-humidifier,
• Co2; Yes, No
If growing Hydro some additional questions:
-DWC? RDWC? Autopots? Ebb and Flow? Other?
-Distance of liquid below net pot (DWC)
-Temperature of reservoir
-TDS of nutrient solution
-Amount of air to solution
Always try to upload a clear picture of any issues you may have to allow the community to assist you. Pictures taken under natural or white lighting are by far the best.
Add anything else you feel would help us give you a most informed answer should be included. Feel free to elaborate, but short and to the point questions and facts will help us to help you in a more efficient manner.
RO water (water with basically 0 ppm) should not be ph balanced.
While it is technically possible to measure the pH of RO (Reverse Osmosis) water.
Doing so accurately can be challenging due to its very low ion concentration aka "ppm/tds, which can lead to unstable readings on a pH meter.
To get a more reliable measurement, you might need to add a small amount of a known ionic solution like “calmag” to the sample to improve conductivity and stabilize the reading.
I add enough calmag to get to 100ppm when I use RO or distilled water.
Knowing the runoff ph as @MidwestGuy ask about and the runoff tds will tell us more.
If the soil ph is still in range and you’ve not given any supplemental nutrients yet, then it could just be time to feed…
Zero ions are present in RO water. Any measure < 50 PPM will wield essentially meter drift.
It is not possible to measure the pH of RO at all with virtually any measurement tool. RO has zero ions, and ions are required for a pH to exist.
Sure you can measure it, you will get a reading from it.
The problem is trusting that reading and then trying to adjust the ph based off that reading so precise as cannabis requires.
Generally it’s agreed that adding just enough of anything to get tds up will give a more accurate reading.
You can test this yourself, if you test distilled water you will get something around 7ph and if you test distilled vinegar you will get something around 2.5ph, although both are below 50ppm.
So depending on the accuracy needed, some applications measuring ph of distilled solutions is no problem.
It’s a problem for growing cannabis because we need such a precise measurement where a few tenths of a ph can make or break nutrient intake.
PH of my water out of the RO system is 7.0 it may be due to the 5th stage that puts the minerals back in. The thing is for me is all these plants get watered at same time with the same mixture only one looks horrible as compared to others. The problem I can’t get past is how to tell if it’s a deficiency or too much especially in regards to cal-mag. That one plant of the 9 is in real bad shape.
I thought you remembered my information from my last grow with getting an Apera PH meter. No disrespect intended. I’m just at a loss as what is affecting that plant.
Have a great day.
Every other feeding is stage 3 Bergmans PHd to 6.5.
I have a primary whole house filter system that takes out the magnesium. Could it be this that is causing the issue and the damage to the plant is severe cal mag deficiency.
It’s simply not physically possible. A pH meter measures the charge balance of the ions present in a solution. No ions exist in RO, therefore no pH can exist.
The only 2 scenarios in which RO can have a pH are:
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Ions are added via adding nutrients, minerals, or other additives, or
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Carbonic acid is present in the solution. If the RO sits out long enough for CO2 to dissolve in the solution in a sufficient quantity, then a pH can exist.
There are too many websites out there that try to keep the definition of pH of distilled or RO simple by stating that they have a pH of 7.0. A 7.0 solution is indeed neutral. RO can also be considered neutral, but the ways in which 7.0 or no pH are neutral are very different.