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so after reading many posts about DONT WORRY ABOUT PH it dosnt matter ,
so the moral of the story is . if your medium climbs too quickly ph your water to bring it down
Some water sources cause the pH of a growing medium to rise rapidly over time. This has nothing to do with the pH of the water, but rather with the alkalinity in the water. Alkalinity is a measure of the bicarbonates and carbonates in the water. Another way to understand water alkalinity is that it is a measure of the ‘’limestone’’ content in the water. The higher the alkalinity, the more ‘’limestone’’ that is being applied, causing the pH of the growing medium to climb. To offset this pH rise, acids are injected into the irrigation water to neutralize some of the alkalinity and reduce the ‘’limestone’’ content in the water. Here are some important tips to consider when choosing an acid.
Table 1. *Relative safety: 1 = fairly safe; 5 = very dangerous **Cost: $ = least expensive; $$$ = most expensive
In the case of nitric acid, this may mean reducing the application rate of an existing fertilizer. If this does not work, then use a fertilizer with a lower ratio of nitrogen to potassium, such as 15-2-20, 15-5-25, 17-5-24, 20-5-30, etc. Remember that using a new fertilizer may have a different influence on the pH of the growing medium.
When using phosphoric acid, higher rates can provide more phosphorus than crops require. Most crops only need 20 ppm P (45 ppm P205), so if enough acid is injected to reduce alkalinity by 50 ppm CaCO3, then too much phosphorus is applied at 27.5 ppm. Extra phosphorus will not harm the crop, but it can lead to stretching and softer growth. If phosphoric acid is used, consider using a fertilizer with no phosphorus, such as 17-0-17, 20-0-20, 25-0-25, etc.
Sulfuric acid provides sulfur in the form of sulfate, which is needed by plants and is often low in water sources and fertilizer programs. Therefore, high rates of sulfuric acid do not cause any issues with the crops as the normal recommended range for sulfur (sulfate) is 25-60 ppm sulfur (75-180 ppm sulfate). For these reasons, and the fact that it is typically the least expensive, sulfuric acid is the choice of most growers.
so the moral of the story is . if your medium climbs too quickly ph your water to bring it down
Some water sources cause the pH of a growing medium to rise rapidly over time. This has nothing to do with the pH of the water, but rather with the alkalinity in the water. Alkalinity is a measure of the bicarbonates and carbonates in the water. Another way to understand water alkalinity is that it is a measure of the ‘’limestone’’ content in the water. The higher the alkalinity, the more ‘’limestone’’ that is being applied, causing the pH of the growing medium to climb. To offset this pH rise, acids are injected into the irrigation water to neutralize some of the alkalinity and reduce the ‘’limestone’’ content in the water. Here are some important tips to consider when choosing an acid.
Selecting an Acid
When deciding which acid to use, there are several factors to consider including safety, additional plant nutrients provided, cost, and availability. The most common acids used to reduce water alkalinity include sulfuric, nitric, phosphoric and citric acids. For these 4 acids: see how much is required to drop the alkalinity of the water by 50 ppm CaCO3, the nutrients provided, relative safety, and cost (Table 1).| Acid | % Active ingredient | Fl. ounces/100 gallons water to neutralize 50 ppm alkalinity | ppm element supplied | Relative safety* | Cost ** |
| Citric Acid (h3C6H5O7) | 50% | 1.78 oz. | None | 1 | $$$ |
| Nitric Acid (h3 NO3) | 67% | 0.87 oz. | 14.3 ppm N | 5 | $$ |
| Phosphoric Acid (H3PO4) | 75% | 0.94 oz. | 27.5 ppm P | 3 | $$ |
| Sulfuric Acid (H2 SO4) | 35% | 1.42 oz. | 16.1 ppm S | 3 | $ |
Nutrients Provided by Acid
Table 1 shows the parts per million (ppm) of the element supplied by each acid. Citric acid does not provide any significant levels of elements. Nitric and phosphoric acids provide needed plant nutrients that are often provided solely by fertilizers. When using a higher rate of an acid, it can provide a significant level of a plant nutrient as seen in Table 1, so a fertilizer with a lower ratio of this element may need to be used.In the case of nitric acid, this may mean reducing the application rate of an existing fertilizer. If this does not work, then use a fertilizer with a lower ratio of nitrogen to potassium, such as 15-2-20, 15-5-25, 17-5-24, 20-5-30, etc. Remember that using a new fertilizer may have a different influence on the pH of the growing medium.
When using phosphoric acid, higher rates can provide more phosphorus than crops require. Most crops only need 20 ppm P (45 ppm P205), so if enough acid is injected to reduce alkalinity by 50 ppm CaCO3, then too much phosphorus is applied at 27.5 ppm. Extra phosphorus will not harm the crop, but it can lead to stretching and softer growth. If phosphoric acid is used, consider using a fertilizer with no phosphorus, such as 17-0-17, 20-0-20, 25-0-25, etc.
Sulfuric acid provides sulfur in the form of sulfate, which is needed by plants and is often low in water sources and fertilizer programs. Therefore, high rates of sulfuric acid do not cause any issues with the crops as the normal recommended range for sulfur (sulfate) is 25-60 ppm sulfur (75-180 ppm sulfate). For these reasons, and the fact that it is typically the least expensive, sulfuric acid is the choice of most growers.
...I'm getting ya.
drill a few holes filled with coco