pH fluctuation in DWC...Yes, I have used the search button...

chadster152

Well-Known Member
Alright so I have two clones in two 5gal. DWC buckets under a 600w MH (dimmed to 300w till they acclimate, got a little bit of bleaching under the 600w). I am using Dyna-Gro Foliage Pro, Dyna-Gro Pro-Tekt, Dyna-Gro Mag-Pro (Haven't used yet), and Botanicare Aquashield. Here is the situation: I did a rez change on Monday, 3/17/14. I added approx. 4 gallons of tap water to each bucket, then the Pro-Tekt, Foliage Pro, and Aquashield, in that order. I pH'd down to 5.8, ppm/ec at ~320/.44. On Tuesday, 3/18/14, I added a large airstone to each bucket. This morning, 3/19/14, at about 8am i checked ph and ppm/ec...pH was 6.7 and ppm/ec rose to ~350/.5. I pH'd to 5.8. I checked again at 1:30pm, ppm/ec rose to ~380/.54 in one bucket and stayed at ~350/.5 in the other, pH was at 6.2. I pH'd back down to 5.5 in both buckets to allow some room for creep...but why is my pH and my ppm rising together? Why is my pH making such large swings in such a short period of time? Any insight is appreciated.

~Chadster152
 

pSi007

Active Member
What is the ppm of TAP water? Tap usually has pH buffers which the plant will never use and will cause the pH to continually rise. You could try an ammonia based pH, like ammonium sulfate. It is the fast and easy, Mad Farmer - Get Down, works well.

http://www.amazon.com/Mad-Farmer-Get-Down-Adjuster/dp/B00CUPUQPC/ref=sr_1_1?ie=UTF8&qid=1395269270&sr=8-1&keywords=mad+farmer+get+down

I use RO water @ 23ppm, I dont use shit like dyna but if I am using hydro and chems, I use my own mix of Monopotassium Phosphate, calcium nitrate, nitric acid, magnesium sulfate, azomite, Iron-Zinc (ch), and water soluble kelp {1-0-18}.

pH is rock-steady... I adjust maybe 1x in 3 weeks.. ;) 27-gallon rez.


ps, my mixes of fertz pwn store shit any day.. 10x cheaper too, fda food grade!
 

chadster152

Well-Known Member
What is the ppm of TAP water? Tap usually has pH buffers which the plant will never use and will cause the pH to continually rise. You could try an ammonia based pH, like ammonium sulfate. It is the fast and easy, Mad Farmer - Get Down, works well.

http://www.amazon.com/Mad-Farmer-Get-Down-Adjuster/dp/B00CUPUQPC/ref=sr_1_1?ie=UTF8&qid=1395269270&sr=8-1&keywords=mad+farmer+get+down

I use RO water @ 23ppm, I dont use shit like dyna but if I am using hydro and chems, I use my own mix of Monopotassium Phosphate, calcium nitrate, nitric acid, magnesium sulfate, azomite, Iron-Zinc (ch), and water soluble kelp {1-0-18}.

pH is rock-steady... I adjust maybe 1x in 3 weeks.. ;) 27-gallon rez.


ps, my mixes of fertz pwn store shit any day.. 10x cheaper too, fda food grade!
My tap ppm is around 200 IIRC. Tap pH is around 7.5ish. That Get Down sounds pretty rad, I'll have to check it out.

Ya you are on some mad scientist shit. I don't have the chemistry knowledge at the moment to pull that off. I chose DG because supposedly it's pretty pH stable.
 

~CReePeR~

Well-Known Member
I have this same issue, I dont know what causes it but it usually settles down after a week or so. Even after you top off the buckets and re adjust the PH to 5.8 it will not venture to far off. once you change the res completely it will do it again.
 

chadster152

Well-Known Member
I have this same issue, I dont know what causes it but it usually settles down after a week or so. Even after you top off the buckets and re adjust the PH to 5.8 it will not venture to far off. once you change the res completely it will do it again.
Do you use airstones?
 

Redoctober

Well-Known Member
What is the ppm of TAP water? Tap usually has pH buffers which the plant will never use and will cause the pH to continually rise. You could try an ammonia based pH, like ammonium sulfate. It is the fast and easy, Mad Farmer - Get Down, works well.

http://www.amazon.com/Mad-Farmer-Get-Down-Adjuster/dp/B00CUPUQPC/ref=sr_1_1?ie=UTF8&qid=1395269270&sr=8-1&keywords=mad+farmer+get+down

I use RO water @ 23ppm, I dont use shit like dyna but if I am using hydro and chems, I use my own mix of Monopotassium Phosphate, calcium nitrate, nitric acid, magnesium sulfate, azomite, Iron-Zinc (ch), and water soluble kelp {1-0-18}.

pH is rock-steady... I adjust maybe 1x in 3 weeks.. ;) 27-gallon rez.


ps, my mixes of fertz pwn store shit any day.. 10x cheaper too, fda food grade!
Very interesting! I never knew that tap water had pH buffers in it. That would certainly explain a few things. I switched to RO water recently but I used to have erratic pH swing too, both to the upside and to the downside. I always thought it must be the plants themselves or the nutrients
 

panhead

Well-Known Member
First off why are you feeding clones at all ? if the plant cant tolerate 600 watts of light its surely too small to feed , if it was me i'd dump the rez & use straight tap water for the 1st week . Unbalanced nutrients & overfeeding will cause the dramatic ph fluctuations your experiencing , your feeding immature clones 4 different produts with one product being a silicate ( Pro-tekt ) which does nothing to enhance plant growth but adds ppm to the solution & if your dead set on using silicates like Pro-tekt they shouldnt be used until plants are vegged well .

Next ya got Aquashield running in the mix which is a compost based nutrient , what does compost do ? it rotts & as it's rotting it's changing the ph along the way & adding more ppm, next your running mag-pro with plants too immature to handle full light but your boosting the cal-mag ratio of the feeding solution & stacking ppm ?, how can i be the only hydroponic grower seeing theese problems with this guys grow ?

Your ph problems are a direct result of overfeeding with both unbalanced nutes & running nutes out of step with plant growth , with such immature plants just use tap water then add 50 ppm dyna grow or foliage pro , then ph .

Seecrest out !
 

chadster152

Well-Known Member
First off why are you feeding clones at all ? if the plant cant tolerate 600 watts of light its surely too small to feed , if it was me i'd dump the rez & use straight tap water for the 1st week . Unbalanced nutrients & overfeeding will cause the dramatic ph fluctuations your experiencing , your feeding immature clones 4 different produts with one product being a silicate ( Pro-tekt ) which does nothing to enhance plant growth but adds ppm to the solution & if your dead set on using silicates like Pro-tekt they shouldnt be used until plants are vegged well .

Next ya got Aquashield running in the mix which is a compost based nutrient , what does compost do ? it rotts & as it's rotting it's changing the ph along the way & adding more ppm, next your running mag-pro with plants too immature to handle full light but your boosting the cal-mag ratio of the feeding solution & stacking ppm ?, how can i be the only hydroponic grower seeing theese problems with this guys grow ?

Your ph problems are a direct result of overfeeding with both unbalanced nutes & running nutes out of step with plant growth , with such immature plants just use tap water then add 50 ppm dyna grow or foliage pro , then ph .

Seecrest out !
I probably should have elaborated more. The cuttings were rooted in a bubble cloner, then grown in coco under a few cfls for about two weeks. They're about 4-5 inches tall...if you click on my signature it'll take you to my grow journal and you can see a bunch of pics.

I haven't added any Mag-Pro yet, its just in the line up. Right now I'm running a 1/4 strength nute solution (w/ aquashield) according to Dyna-Gro's non-recirc hydro feed sheet. How is it unbalanced??
 

chadster152

Well-Known Member
Yes I am using airstones, Check PH everyday and get it back to 5.8
That's what I've been doing. It's starting to mellow out though...I checked last night at 1:30am, pH @ 5.9...checked again this morning at 8am, pH at 6.0 & 6.1...just gotta keep an eye on it I guess.
 

SableZen

Well-Known Member
Next ya got Aquashield running in the mix which is a compost based nutrient , what does compost do ? it rotts & as it's rotting it's changing the ph along the way & adding more ppm, next your running mag-pro with plants too immature to handle full light but your boosting the cal-mag ratio of the feeding solution & stacking ppm ?, how can i be the only hydroponic grower seeing theese problems with this guys grow ?

Your ph problems are a direct result of overfeeding with both unbalanced nutes & running nutes out of step with plant growth , with such immature plants just use tap water then add 50 ppm dyna grow or foliage pro , then ph .

Seecrest out !
AquaShield isn't a nutrient or compost. It's strains of beneficial bacteria ("compost derived" but has no compost) and hasn't ever had any noticeable impact on reservoir pH in my setup.

Also, I put rooted clones straight into the same strength nutrient solution as the plant it was cut from was in (even root the cuttings in the same nutrient solution) without issues - I don't treat them like seedlings or anything.

What are you using to adjust your pH chadster?
 

chadster152

Well-Known Member
AquaShield isn't a nutrient or compost. It's strains of beneficial bacteria ("compost derived" but has no compost) and hasn't ever had any noticeable impact on reservoir pH in my setup.

Also, I put rooted clones straight into the same strength nutrient solution as the plant it was cut from was in (even root the cuttings in the same nutrient solution) without issues - I don't treat them like seedlings or anything.

What are you using to adjust your pH chadster?
Thank you for clarifying on Aquashield, that makes more sense as I've never heard of it doing anything but work properly for anyone who's used it.

I am using aquarium pH up & pH down...I was in a pinch, need some pH up and down, but it was 8pm and all the hydro stores were closed. It says it's safe for plants and fish. The only drawback is that it's super concentrated. I spilt some pH down on my arm the first night I got it, immediately rinsed with cool water, and I still got an acid burn. I usually use about 1/4 tsp to adjust from low to mid 6's down to mid to high 5's.
 

chadster152

Well-Known Member
too much airflow can cause pH swings FYI
I think that is what started this whole thing. I added an airstone to each bucket and then it began. It has mellowed out though...took a pH reading at 12:30pm, both buckets rock solid at 5.8.
 

SableZen

Well-Known Member
Thank you for clarifying on Aquashield, that makes more sense as I've never heard of it doing anything but work properly for anyone who's used it.

I am using aquarium pH up & pH down...I was in a pinch, need some pH up and down, but it was 8pm and all the hydro stores were closed. It says it's safe for plants and fish. The only drawback is that it's super concentrated. I spilt some pH down on my arm the first night I got it, immediately rinsed with cool water, and I still got an acid burn. I usually use about 1/4 tsp to adjust from low to mid 6's down to mid to high 5's.
Yeah I'm not sure what aquarium pH up & down are, or if they even differ from what is commonly used in hydroponics. I'd imagine it's probably safe for plants but wonder if it might not be as effective in a nutrient solution. Just out of curiosity, if you get the chance look on your bottles and see what the active ingredient(s) are.
 

pSi007

Active Member
Very interesting! I never knew that tap water had pH buffers in it

nasty alky ones too in order to prevent the pipes from rusting. With calcium nitrate, you don't want tap water, the monoPK will contain the bulk of ammonia discharge, great chit..

300ppm of pH buffers @ 7.5 can get nasty.! :weed:



edit: Here is some MonoPK at wholesale. Beastie bloomz, open seas, kool bloom, most chit uses MonoPK but charges 10x more for it.here is 5lbs of pure 0-52-34 for $20, at 86% PK plant fuel, very little will "salt-toxic" your plants.. I use about 1tsp per gallon in bloom, ppm @ 1300, coco flood.

http://www.amazon.com/Potassium-Phosphate-Fertilizer-Monopotassium-Hydroponics/dp/B00HCS99YG/ref=sr_1_1?ie=UTF8&qid=1395360778&sr=8-1&keywords=monopotassium+phosphate
 

pSi007

Active Member
What causes tap water to be prone to pH swings? The additives (fluoride, chlorine, etc) my local water company adds? or is it just the mineral content?
"Buffering capacity refers to water's ability to keep the pH stable as acids or bases are added. pH and buffering capacity are intertwined with one another; although one might think that adding equal volumes of an acid and neutral water would result in a pH halfway in between, this rarely happens in practice. If the water has sufficient buffering capacity, the buffering capacity can absorb and neutralize the added acid without significantly changing the pH. Conceptually, a buffer acts somewhat like a large sponge. As more acid is added, the "sponge" absorbs the acid without chaning the pH much. The "sponge's" capacity is limited however; once the buffering capacity is used up, pH changes more rapidly as acids are added."

http://www.cs.duke.edu/~narten/faq/chemistry.html
 
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