PLEASE help - PH changes in water

I use an auto drip feeder that comes from a 5 gallon bucket. I only add one gallon of water into it and then add another when it gets low (about 1 gal every day or two). I am PHing my water/nutes to 6.5. I am noticing that the PH rises once it is in the bucket for a while. This morning is was around 7.4.


Does anyone have any experience on how to manage this? Should I PH it down to 6 instead of 6.5 before adding to account for the rise?

What nutrients are you using? , maybe something you are using might be causing the pH problem..

Your water temp is prob too high, that will cause a drastic fluctuation in ph

I am using Fox Farms trio. But I am PHing after I add them. Temps stay pretty good. 75-80 max and cool off at night.

water temp to high cause the problem and also tap water will do the same if its a drip system try moving the res out of grow room to cooler place .make and exsperment get another bucket fill it the same as the other in grow room put in cooler place for 24 hours check phs in both see what happens if cooler one is also high problaly the water being use but in my experince tap water sucks for hydro ph gos to high also high water temp does the same

Water temp too high, plants drinking more than eating or the ppm of your mix is too weak. One of those three things is most likely your issue.

My water does this too. I let it warm at room temperature [for at least 6 hours and usually 24] before mixing and adjusting and yet the next day the pH rises [before it is ever used]. If I mix only small batches of nutes the problem isn't as pronounced. I'm talking a change of about 0.7 pH units in two days (5.8 to ~ 6.3). I've always attributed this to the phos level of my raw water (0.14 ppm). I just pH down it back to normal before I use it.

My water has usually sat out without nutes for a few days before use. I am experimenting right now. I mixed up a nute solution a few hours ago. I am curious to see if the PH changes after a few hours before I adjust. Well, I should have taken a fresh PH reading first, maybe I will next time. But the test was to see if the PH is more stable tomorrow if I adjust and add to my bucket tonight.

So water went in to my 5 gal bucket last night at around 6:00. I emptied it first to make sure I had no residue. The PH at that time, after mixing nutes in hours earlier, was 6.0. This morning it had risen to 6.7. Temps in tent during those hours would have ranged 65-75 at most. One thing I did notice, despite the fact that I am using liquid nutes, they do settle. When I went to PH them there was a clear color difference between the bottom and top of the water jog. I mix by just shaking it up, curious of others use a whisk or something????

GrowinDad said:

So water went in to my 5 gal bucket last night at around 6:00. I emptied it first to make sure I had no residue. The PH at that time, after mixing nutes in hours earlier, was 6.0. This morning it had risen to 6.7. Temps in tent during those hours would have ranged 65-75 at most. One thing I did notice, despite the fact that I am using liquid nutes, they do settle. When I went to PH them there was a clear color difference between the bottom and top of the water jog. I mix by just shaking it up, curious of others use a whisk or something????

Click to expand...

I'm using a small submersible pump (aquarium fountain type) to agitate my solution it work 24/24 & use only 13w.

GrowinDad said:

I use an auto drip feeder that comes from a 5 gallon bucket. I only add one gallon of water into it and then add another when it gets low (about 1 gal every day or two). I am PHing my water/nutes to 6.5. I am noticing that the PH rises once it is in the bucket for a while. This morning is was around 7.4.


Does anyone have any experience on how to manage this? Should I PH it down to 6 instead of 6.5 before adding to account for the rise?

Click to expand...

What's the Ph of your water, with out mixing nutrients? Your pump is in the 5 gallon bucket?

PH of my water after sitting out a couple days to remove chlorine is about 7.8. I don't actually use a pump at all, though I do have a large airstone to keep it oxygenated. I am using the Tropf Blumat System (http://www.planetearthhydro.com/tropf-blumat-self-watering-system-12-piece-kit/) which is basically gravity fed, just a tube at the bottom of the 5 gal bucket that goes to all my plants. The little ceramic cones detect when moisture is below wherever you calibrate it. From there it drips until it reaches hte desired point. It's pretty cool for taking guesswork out of feeding, great if you are going out of town a few days, but I am also seeing hte drawback as I can't go straight from PHd water to getting it to the plants.

I PHd my soil today as well and it was around 6.8, not ideal but not scary. I think if I continue to add water PHd around 5.8-6.0 it will help. I only have a few weeks to go on this grow and then I will figure out improvements for next time.

Your water is the problem. It doesn't sound like there using chlorine gas, but chloromide in your water. Chlorine gas has a half life of 12hours in water. The chloramine is designed to stay in your water for a long time. You could use a aquarium water conditioner. It will neutrallize the chloramine, but will leave some amonia in your water from the process.
you should research "Ph rebound" it will help you in knowing whats going on with your ions in your solution, and how they make your Ph rebound back to a neutral Ph.
You only have a couple of weeks left. Try a gallon or two of distilled water. It will make it alot easier. You might have to think about a water filtering system in the future.

Put a small pump in your rez. I you use ro water you will need to add calcium and magnesium back in.

If I add the pump, do you think I still need the airstone or will the pump add enough from the agitation. I am out of electrical outlets in my tent.

What top fuel siad.

GrowinDad said:

I am using Fox Farms trio. But I am PHing after I add them. Temps stay pretty good. 75-80 max and cool off at night.

Click to expand...

I am also using Fox Farms and would like to know if you mix your nutrients and let them sit in your bucket for a period of time? I let a mixed jug of nutrient mix sit for a day and then tested the PH and it had actually dropped.

The reactions take time. A pump which moves water around decreases that time. If you mix, give it a quick stir, and check PH, it is bound to have shifted after a day.

I do, sort of. My plants are self feeders. So the water is always sitting there and they take a drink when they want. I did start to mix up the nutes in a gallon jug hours before I dump them into my "resevoir"/bucket. There is no doubt that they settle. After sitting for a few hours, you can see color difference between top and bottom of the water jug. I am going to give Dyna-Gro, non-organic, a try on my next grow and see if they behave any better for settling as well as PH consistency.

I'm not ready to invest in a RO system. I already have a pur faucet filter in my kitchen so I am going to use it. It appears as though it does remove chloramine. I just bought a pump to keep the water moving and hopefully avoid the settling while it is in my bucket waiting for the plants to take a drink and keep everything mixed together. Unfortunately the fucking thing doesn't work so it is back to the pet store for me in a few minutes

I did a little test today on PH to see what happens. My water out of the Pur filter was 7.04 It went down to 5.5 when I added nutes (1T Big Bloom and 2t Tiger Bloom). Those were at 9:00 EST this morning. At 3:00 EST this afternoon, ithad only risen to 5.61 which I will consider margin of error on my digital PH meter that is always a little off calibration. Sp they stayed pretty stable. This is different than I experienced before. Only differences were that last time I also had Grow Big in the mix and did not use the Pur filter...