PH Constantly Rising

Hi all,

I have a DWC setup with 5 gallon buckets. I'm using tap water and I can't keep the PH stable. Everything I read claims that the airstone won't cause the PH to increase, but I swear that's what the problem is. Tap water starts out at ~7.2 I'll add nutrients, hydroguard, and calmeg before adding PH down. I'll leave it at 5.9 only for it to jump up to 7.8/8.0 a few hours later. I tested with a spare bucket adding everything one by one and then checking a few hours later to see if it changed and everything was stable until I added the airstone. Nothing I've read thus far has been helpful. Has anyone had this issue before or perhaps have insight into why adding the airstone causes the PH to increase? Any help or advice is appreciated.
 

TintEastwood

Well-Known Member
Rise is not uncommon with airstones. The quality of air being sucked into the pump and injected via the airstones matters.

What ph down are you using?
 
Rise is not uncommon with airstones. The quality of air being sucked into the pump and injected via the airstones matters.

What ph down are you using?
Thanks for the reply!! I'm using General Hydroponics PH down liquid. Is there a way to get better air quality going in or something that can be done to stabilize the PH? As it is now I may have to figure out another setup because I think the PH swings are way too much.
 

rkymtnman

Well-Known Member
when you did this with a spare bucket, was there a plant in it? or just the nutes?

the airstones do contribute to pH rise but roots constantly submerged also plays a part. as does the small volume of water which in a 5 gal bucket is really more like only 3 gals.
 
when you did this with a spare bucket, was there a plant in it? or just the nutes?

the airstones do contribute to pH rise but roots constantly submerged also plays a part. as does the small volume of water which in a 5 gal bucket is really more like only 3 gals.
There was no plant in the spare bucket. Everything was stable until I put in the airstone. I was expecting some fluctuations in PH but not so much and so fast. About an hour after adding the airstone the PH jumps up 7+.
 

myke

Well-Known Member
Ya this is normal. As you increase ppm it’s seams to be more stable. A trick I learned from a fella here was to add ph up at about 1.5ml per 5 gallon. Then add the ph down. The up works as a buffering agent and seams to keep the ph from fluctuations.
 

MrGreenFingers99

Well-Known Member
Hi all,

I have a DWC setup with 5 gallon buckets. I'm using tap water and I can't keep the PH stable. Everything I read claims that the airstone won't cause the PH to increase, but I swear that's what the problem is. Tap water starts out at ~7.2 I'll add nutrients, hydroguard, and calmeg before adding PH down. I'll leave it at 5.9 only for it to jump up to 7.8/8.0 a few hours later. I tested with a spare bucket adding everything one by one and then checking a few hours later to see if it changed and everything was stable until I added the airstone. Nothing I've read thus far has been helpful. Has anyone had this issue before or perhaps have insight into why adding the airstone causes the PH to increase? Any help or advice is appreciated.
Mine does it by the same amount every time in my setup, always rises by 0.8 so I set my my ph to 5 when mixing nutes - next day its 5.8 and stabilises, then either stays where it is or rises slightly over the cause of the week.
 

Rahz

Well-Known Member
Hi all,

I have a DWC setup with 5 gallon buckets. I'm using tap water and I can't keep the PH stable. Everything I read claims that the airstone won't cause the PH to increase, but I swear that's what the problem is. Tap water starts out at ~7.2 I'll add nutrients, hydroguard, and calmeg before adding PH down. I'll leave it at 5.9 only for it to jump up to 7.8/8.0 a few hours later. I tested with a spare bucket adding everything one by one and then checking a few hours later to see if it changed and everything was stable until I added the airstone. Nothing I've read thus far has been helpful. Has anyone had this issue before or perhaps have insight into why adding the airstone causes the PH to increase? Any help or advice is appreciated.
Plants release ions into the water when they uptake nitrate nitrogen that causes the PH to go up. Some nutrient formulas buffer for this better than others but 7.8-8.0 is pretty extreme. Using a nutrient with no buffers I can expect the PH to hit 6.5-6.8 in a day or two so I'm not sure what's causing it. Not the air stone unless it just had some base residue in it from production. Assuming that's the case, I'm curious what happened after adjusting the PH again. If it still rises that would take the airstone out of the equation IMO.

There are microbial products that will notably increase PH but with hydroguard being a liquid I'm not sure that's the issue since it's the clay filler used in the microbe powder that causes the PH increase.
 

its.always.420

Well-Known Member
Thanks for the reply!! I'm using General Hydroponics PH down liquid. Is there a way to get better air quality going in or something that can be done to stabilize the PH? As it is now I may have to figure out another setup because I think the PH swings are way too much.
i had problems with GH up/down and switched to AN ph products. They're stupid concentrated and it works much better. Not saying that's your problem but it might help. Oh and ya put calmag in first.
 
I finally got some time to try some of the suggestions that you guys gave to no avail. I tried myke's suggestion to add PH up, to be used as a buffer, before adding PH down and the PH still increased to 7+. Even if I get the PH to 5 it still increases to 7+ a few hours later. I'm positive it has something to do with the airstone or maybe with the air that's being pumped. Someone suggested on another site to build a "hepta filter box" to place the air pump in. When I get the time I'll try that out.

I don't see what else it could be. Unless perhaps the hydroguard or nutrients are interacting with air somehow and causing the PH to increase. I rinsed the airstone out thoroughly. The PH is stable as can be until that airstone goes in. I just wished I had this all figured out before I started my seedlings. But this is a different setup than I used in the past. Did not expect this.. I'll let you guys know how the hepta box works out.

I appreciate very much all your help and thanks for telling me about the CalMag as I didn't know that needed to go in first.
 

myke

Well-Known Member
I finally got some time to try some of the suggestions that you guys gave to no avail. I tried myke's suggestion to add PH up, to be used as a buffer, before adding PH down and the PH still increased to 7+. Even if I get the PH to 5 it still increases to 7+ a few hours later. I'm positive it has something to do with the airstone or maybe with the air that's being pumped. Someone suggested on another site to build a "hepta filter box" to place the air pump in. When I get the time I'll try that out.

I don't see what else it could be. Unless perhaps the hydroguard or nutrients are interacting with air somehow and causing the PH to increase. I rinsed the airstone out thoroughly. The PH is stable as can be until that airstone goes in. I just wished I had this all figured out before I started my seedlings. But this is a different setup than I used in the past. Did not expect this.. I'll let you guys know how the hepta box works out.

I appreciate very much all your help and thanks for telling me about the CalMag as I didn't know that needed to go in first.
This is normal for me,ppm must be low?As you go higher it will stay lower.Best is to not panic,dont go adding a bunch of ph down.Best advice is to not check pH much your small plants will be fine at 6.5.let it run for 24 hrs and see.1ml ph down per litre of water gives 1 ppm just so ya know.
 

Latavius Janikowski

Active Member
This is an interesting thread. I'm curious if you guys have ever used the Aerogarden Liquid Plant Food as nutrients and if so, do you also add pH down? I've used an aerogarden for years to grow herbs and lettuce and it kicked ass, so I tried growing a couple plants and they're going great! I just unhooked the aerogarden light and used a 1000w led. However, I'm always curious to know how to improve. Here are some pics. I have tried to mimic the aerogarden concept, just using 5 gallon tubs, so there's a pic of that as well. The aerogarden obviously was way too small for the plants, but they still killed I think for my first grow! Lmk what you think and how close!

0C86757A-5342-4DE5-BFFA-B8803FAAA06C.JPEGA6A4380A-7E3B-4960-B029-DAEE34A56EF2.JPEGEAAAB08E-C13C-4189-A5B1-0243F9C1AACE.JPEG2C0A18EE-BFB2-4F62-8619-B9C36B55393A.JPEG063AB073-582D-4031-932A-38C1C7DF3DE5.JPEGD6098510-2621-4043-ADCC-2EE71774A24F.JPG
 
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