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The Importants of Ph..
PH stands for Potential Hydrogen. All Hydroponic nutrient solutions need to be kept at the proper PH if they are to be used by the plants. All the Hydroponic nutrients in the world will do a plant no good if it cannot absorb them easily. A major factor in determining a plant’s ability to uptake Hydroponic nutrients is the relative acidity, or PH (Potential Hydrogen) of the Hydroponic growing medium or Hydroponic solution from which they feed.
PH is measured on a scale of 1-14 and represents the concentration of hydrogen ions in solution. Generally, it is used to determine whether a Hydroponic solution is acidic or basic. A 1 on the scale represents a low ion concentration or acid. Pure water has a balance of Hydrogen and Hydroxyl ions. Pure water is considered neutral at a pH of 7. A 14 on the scale represents the highest concentration of ions (basic, alkaline).
Some Hydroponic nutrients may become unavailable to the plant if the Hydroponic nutrient solution PH drifts from an optimal reading, which for most plants is between 5.5 and 6.5. This condition is called nutrient lockout. If you regularly monitor the PH and the PPM (parts per million) of the Hydroponic nutrient solution you will have the ability to make corrections to your Hydroponic solution for optimum plant growth.
An unusually high PH will decrease the availability of Iron, Manganese, Boron, Copper, Zinc and Phosphorus. A PH that is too low will reduce the availability of Potassium, Sulfur, Calcium, Magnesium and Phosphorus. PH is one of the most important factors in Hydroponic gardening. It makes your nutrients available to your plants. If you are feeding your plants from a re-circulation nutrient tank change the nutrient solution every 10 to 14 days and stop all nutrients 3 to 14 days before harvesting edible plants or fruits.
You can use any leftover Hydroponic solution to water your house plants or other outside yard plants. The PH in your nutrients can change as plants uptake what they need from the Hydroponic solution and it returns into the tank. Normally the PH in your Hydroponic nutrient solution will go higher as the Hydroponic nutrients are utilized by the plants. When you add Hydroponic nutrients to your tank the PH usually will go down.
There are several products on the market that you can use to quickly and easily adjust the PH in your Hydroponic tank up or down as needed. We like to use PH up and PH down by Earth Juice. It is simple and clean and uses all natural ingredients to change the PH in either direction. The PH up uses crystallized potassium bicarbonate and the PH down uses crystallized citric acid.
Both these dry products work extremely well and you only use a tiny bit to make the PH changes in your Hydroponic nutrient tank so it really goes a long way. We would rather use these simple natural dry products then some of the more caustic liquid PH adjusters out there. Read further to see how simple it can be to check the PH of your Hydroponic nutrients and make the simple adjustments to it.
The Importants of Ph - How to Test
The PH in Hydroponic Nutrients solutions can be easily checked and monitored with a simple PH tester like this one. There are many models and price ranges of PH meters available.
This is one of the least expensive models by Milwaukee and it works great every time. It has a single calibration setting that makes it super easy to use. Ours has been set once and has never had to be readjusted since. To check that the pH meter is calibrated correctly you just remove the black cap and put it in a little 7.01 PH solution that comes with the unit. If it reads 7.0 it is calibrated correctly and ready to use.
Even that does not have to be done with our unit very often because it always remains the same. It is very accurate at giving the PH readings in the Hydroponic solutions.T
his is also a great PH meter for testing water quality as well as all Hydroponic solutions. You just turn it on and dip it into your Hydroponic nutrient solution and stir. It has a range of 0.0 to 14.0 and you can even use it to test the PH in soils. To test soils just mix 2 parts of distilled water with 1 part of soil. Stir this mix and let the soil settle. Then test this water to get the PH value of your soil.
It has a very fast reading response and is very easy to use. It comes with its own batteries and they are supposed to last up to 700 hours. This little tool makes every Hydroponic gardener's job much easier and is a must have tool for all Hydroponic nutrient solutions. Read further and we will give you an example of testing a Hydroponic nutrient solution so you see how it works and how simple it really is.
Hydroponic Ph Levels - Example
This is how it all works. We will do an actual Hydroponic nutrient tank experiment.
In this experiment we will show what can be expected as changes in a Hydroponic nutrient solution as far as PH and also the PPM (parts per million) strength of our Hydroponic nutrient solution. In this example we will use our little Hydroponic Ebb and Flow system we built earlier on as the experiment. We will be using Hydroton as the growing medium and we will be using Dyna-Gro 7-9-5 Grow nutrients as the Hydroponic nutrient solution. We will also be using a 4 gallon nutrient tank to hold the solution in.
Hydroton does not hold nutrient solution for very long as compared to a growing medium like Coco peat. We know this because it dries out fairly fast and after flooding the container the water level in the Hydroponic tank will be almost exactly where it was when it started. Hydroton does allow for lots of oxygen and carbon dioxide to the root zone though which is very good for the plants.
Our experiment starts using 4 gallons of water that has a PH of 7.4. Many city and county water facilities put out water in the ranges of anywhere from PH 7.2 all the way up to PH 9.0. Yours may be different from ours. Now we will add 4 teaspoons of the Dyna-Gro nutrient solution that will immediately lower the PH down to 5.9 and give us a Hydroponic nutrient strength of 500 PPM. There are no plants in the Hydroponic system, just the Hydroton.
The growing container has about 10 pounds of Hydroton in it and it takes 6 minutes to fill with the small pump we have chosen to use in the Hydroponic nutrient tank. We will flood and drain this Hydroponic growing container 5 times a day for 30 minutes each time to simulate actual growing conditions and we will do this for 5 days. On the fifth day we find that the PH of the Hydroponic nutrient solution has drifted up from PH 5.9 to PH 7.0 and our Hydroponic nutrient strength has drifted down to 300 PPM. Both the PH and the PPM of our Hydroponic solution has changed and there are not even any plants in the system. What has happened here?
Both our Hydroponic nutrient solution readings have changed because in the course of 5 days we have lost about 1/2 gallon of Hydroponic nutrient solution to evaporation. We know this for sure because we have marked the inside of the Hydroponic solution tank in one gallon increments and we know the solution level is now about 1/2 gallon lower. Some of the Hydroponic nutrients may also be stored in the Hydroton balls as well which would help to raise the Ph in the tank.
How do we fix our Hydroponic solution? Very easy. By adding 1 teaspoon of the Dyna-Gro Hydroponic solution we bring our Hydroponic nutrient solution back up to 500 PPM and our PH down to 6.8 with this one action. Adding 1 more teaspoon of the Dyna-Gro will increase our strength to 650 PPM and lower our PH to 6.5. We did not add any water which is why we have now a Hydroponic solution strength of 650 PPM and not 500 PPM. With this example I think you can see how this all works. If there were plants in the Hydroponic system this would certainly all change. Whenever plants uptake Hydroponic nutrients, the PH will change quite a bit.
What is really happening within our Hydroponic system is this: Whenever nutrients are removed PH goes up and PPM goes down. If you could remove only the water and leave the nutrients the exact opposite would happen. All of this monitoring and checking and changing of the PPM and the PH of the Hydroponic nutrient solution can all be done very easily with a Truncheon meter and A PH meter. Every time you do an action you just check it again.
The PH can also be changed in a Hydroponic solution by adding a tiny bit of the PH up or PH down adjusters. We always check the PPM of the Hydroponic solution first because bringing up the PPM to the correct level may also correct or partially correct any PH problem in the Hydroponic solution. If it does not correct it all the way just use a little PH adjuster and you are there. Get some helpful information on growing mediums, grow lights and actual plant growing data in the other sections of this site.