I’m on my 2nd grow (7th week w/ autoflowers) and I’m running into pH issues. First grow I was using about 300-400% more pH down per gallon of water. Things are getting so acidic now the next time I water I’m going to use pH up. I’m wondering, is carbon filtered city tap water (not well water) known to fluctuate with the seasons? To make it simple, my tap water comes from Lake Michigan. Does Lake Michigan become more acidic in the winter? Is there something I’m not thinking of that happens when it’s cold out that makes tap water more acidic?
I tested with an Apera PH20 digital meter multiple times and calibrated it every time. I also used the pH test kit drops that come with the pH kit you can get on Amazon and everything lines up. pH down gets added last so it’s not that newbie mistake.
I have a plan to bring the pH up, I’m just wondering how the pH of my soil (FFOF) got so low (5.8ish) when I always test pH and whatever I’m feeding has never been below 6.3. Up until ~2 weeks ago the only other thing besides water that went into the soil was Recharge and maybe 1 ML total of cal/mag.
I know you’re supposed to wait to see the effects of pH down when using hydroponics but I didn’t think that was the case when you were just putting it into a gallon of water. Are you supposed to let it sit for 30 minutes or something before you test pH? Like it’s showing 6.5 right after I put it in but 30 minutes later when it’s sitting in the soil it’s actually at 5.5 or something?
Thanks for any advice. My first grow wouldn’t have been a success had it not been for the DGC 🙂
The pH of your city water shouldn’t fluctuate too much. Unless their water source or sterilization processes change. A solutions pH stability will depend on a few variables like the mineral ratios, concentrations and the volume of water.
Often water sources for cities change depending on certain aspects like work going on, water levels and other things like this.
Mine does the same thing comes out around 7 can rise as high as 9 if I let it sit a couple days to dechlorinate usually around 8 though. It is super weird. I ph down to 5.6 to be safe. I have never seen mine drop though once it sits only rise.
It depends a lot on where your water is coming from, but tap water conditions can definitely change with the seasons. I think most water companies do their best to keep things consistent, but conditions can vary quite a bit.
Water levels in local rivers and reservoirs can vary a ton based on seasons and the weather. This can effect both water quality and where your water company is pulling its water from.
For example, water might come from a lake or river during the winter when water levels are high, and then during the dry summer months you might get more water from wells or underground aquifers.
A really rainy year can also add a lot of water (and also organic material) to the system and can lower pH. A really dry year on the other hand might mean more water is pulled from underground, which could raise pH and mineral content.
It all kinda just depends on your location and how your local water system is setup.
Water is life tho! I encourage everyone to learn about the water system in their area and get involved in local water issues. This stuff really matters to peoples health and the environment, so get involved!
Just wanted to say thanks for all of the advice. And Soup, I’m not sure if I saw this here, but I used this resource to find out more about my tap water: https://www.ewg.org/tapwater/