GrowinSmoke
Member
I posted this in General Growing, but I am guessing those of you who can explain this hang out here. Educate me!
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I was having some (presumably) pH issues with a couple of small plants. They looked pretty much finished, but somehow bounced back. I was getting pretty severe lockouts with and without nutrients Early signs of deficiency would show up within a day of watering, would progress quickly for a couple days, and then the plant would resume growth and mostly recover as the soil dried out. For a few waterings it was 2 steps forward, 1 step back.
This is the first time I have used distilled water early in veg. My first grow used tap water (I let the chlorine evaporate first), and my second used RO with mixed results until the last couple weeks before harvest when I started using distilled water. I have also never monitored or adjusted pH until this grow when the issues started. The soil used on each grow is a Miracle Grow seed starting mix. It is nearly empty of nutrients, and should be "safe". I started mixing perlite at ~30% in the second grow, and I added some Espoma biotone starter when I re-potted a couple weeks ago. I have no reason to believe there is any differences in the soil across these grows that explain why I have issues now and not before. I will admit there is much better soil out there, and I will be re-potting in something different when the time comes.
After I got my meter, I watered a soil sample and found the pH 6.8 distilled water was resulting in a runoff pH of 4.9-5.0. Eventually this runoff would stabilize around 6.5-7.0. I repeated the test with my light dose of Biothrive Grow(2tsp/gallon) and CaMg+(1tsp/gallon). This nutrient solution pH level was measured at 5.1, and the runoff was also about 5.0. The only difference was the runoff pH seems to stabilize at no higher than pH 5.3 after sitting for close to 2 hours.
I repeated these tests, but this time armed with some aquarium pH up. I expected a pH increase of 0.2 over 6.8 when I added 2 drops per gallon, but measured pH 8.8 steadily over the next few days. I also looked at my city's water test results and found we have a pH of 9.5. I then confirmed the pH on the tap water in my home to be 9.3. My first plant grew so well, maybe the high pH was to thank?
I found my nutrient solution made with the pH 8.8 distilled water, as well as the solution made with my tap water, measures at the same pH as the solutions made with the pH 6.8 water. I suppose there are probably some type of active buffers in the nutrients that make this happen. My pH runoff is also the same 5.0-5.3 it was with the pH 6.8 distilled water.
Now here is the part I find most interesting; I watered a plant 3 days ago with the pH 8.8 distilled water nutrient solution, and she is looking very good! This is the first time since she was 2 inches tall I have watered without causing problems. For the sake of science, I decided to make a nutrient solution with my tap water and watered another plant today with it. We will see how that turns out. Hopefully It's not just a lucky fluke.
It seems as if the pH of the base water still has some sort of relevance, even after the solution's pH is changed by the nutrients. Has anyone experienced this before? I would love to understand what is going on here.
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I was having some (presumably) pH issues with a couple of small plants. They looked pretty much finished, but somehow bounced back. I was getting pretty severe lockouts with and without nutrients Early signs of deficiency would show up within a day of watering, would progress quickly for a couple days, and then the plant would resume growth and mostly recover as the soil dried out. For a few waterings it was 2 steps forward, 1 step back.
This is the first time I have used distilled water early in veg. My first grow used tap water (I let the chlorine evaporate first), and my second used RO with mixed results until the last couple weeks before harvest when I started using distilled water. I have also never monitored or adjusted pH until this grow when the issues started. The soil used on each grow is a Miracle Grow seed starting mix. It is nearly empty of nutrients, and should be "safe". I started mixing perlite at ~30% in the second grow, and I added some Espoma biotone starter when I re-potted a couple weeks ago. I have no reason to believe there is any differences in the soil across these grows that explain why I have issues now and not before. I will admit there is much better soil out there, and I will be re-potting in something different when the time comes.
After I got my meter, I watered a soil sample and found the pH 6.8 distilled water was resulting in a runoff pH of 4.9-5.0. Eventually this runoff would stabilize around 6.5-7.0. I repeated the test with my light dose of Biothrive Grow(2tsp/gallon) and CaMg+(1tsp/gallon). This nutrient solution pH level was measured at 5.1, and the runoff was also about 5.0. The only difference was the runoff pH seems to stabilize at no higher than pH 5.3 after sitting for close to 2 hours.
I repeated these tests, but this time armed with some aquarium pH up. I expected a pH increase of 0.2 over 6.8 when I added 2 drops per gallon, but measured pH 8.8 steadily over the next few days. I also looked at my city's water test results and found we have a pH of 9.5. I then confirmed the pH on the tap water in my home to be 9.3. My first plant grew so well, maybe the high pH was to thank?
I found my nutrient solution made with the pH 8.8 distilled water, as well as the solution made with my tap water, measures at the same pH as the solutions made with the pH 6.8 water. I suppose there are probably some type of active buffers in the nutrients that make this happen. My pH runoff is also the same 5.0-5.3 it was with the pH 6.8 distilled water.
Now here is the part I find most interesting; I watered a plant 3 days ago with the pH 8.8 distilled water nutrient solution, and she is looking very good! This is the first time since she was 2 inches tall I have watered without causing problems. For the sake of science, I decided to make a nutrient solution with my tap water and watered another plant today with it. We will see how that turns out. Hopefully It's not just a lucky fluke.
It seems as if the pH of the base water still has some sort of relevance, even after the solution's pH is changed by the nutrients. Has anyone experienced this before? I would love to understand what is going on here.
