dropping PH

[surfinc]

I usually have rising ph in my resi tank. This last two weeks it has been dropping between each feeding.
Looking for experince with dropping ph..
Adv Nutrients 3 part
Bud Candy
Carboload
semsizym
bigbud
b-12
Any help would be appreciated..

 

[surfinc]

http://www.marijuanapassion.com/forum/attachment.php?attachmentid=176864&d=1316963914
i found this...can somebody explain catons to me?

 

[ozzydiodude]

catons are uncombined elements

 

[surfinc]

i think iasked the wrong question...seems for long time i have been taking in anions... now for the first time seems i am taking in cations....
Anybody have help here ?
What or why anions in the past and now cations??

 

[Hushpuppy]

It sounds like you may be developing toxicity from chem buildup. The plant will take in and exchange both cations and anions depending on what it needs and what the pH is at any given time. But over time, if there is a lot of "synthetic" nutrients used, the chemical left-overs will build up and cause problems.

I don't generally worry about the cations and anions as that goes to the chemistry of how the plants absorb nutrients. I have found that by keeping the chemical left-overs from building up and allowing the pH to drift within a "zone of tolerance" that the chemistry takes care of itself and the plants grow happily along.

What kind of medium are you using? What AN 3part nute? How old are the plants? do you/have you flushed them?

 

[surfinc]

base micro grow bloom.
I flushed more often this cycle due to the change,
Honestly never used PH up before ...it always has raised gradually through the resi..until change..
I use rockwool 4 inch on slabs
plants look good...23 days left in 63 day flower...J1 strain...roughly 10th time through with this ...
not worrying just trying to learn why or what differences could cause the variation..

 

[trillions of atoms]

Its dropping because they are feeding good and pulling water out. Increasing the buffers and concentrating the solution...you end with a lower ph. I add r/o to combat.

try and let the solution do its thing w as little dosing as possible to correct ph.

low ph could be nutrient ppm to high

high ph or unstable =low buffer and weak solution.

How old are plants?

Its normal

 

[trillions of atoms]

Some run drain to waste for this reason in rockwool

 

[Hushpuppy]

I wonder about the nutes you are using. I use AN's Jungle Juice which is a 3part but it doesn't have the pH buffers in it. While I have to do my own pH adjustments, I don't have pH issues or any kinds of salt buildup. I always do one flush at the end of the 3rd week of flower and that keeps everything straight. But I have always had the pH in my grows to drop over time rather than rise over time. I just set it around 6.0-6.3 and then let it go for 3-4 days, then when I check it, it has dropped to around 4.5-5.5 and they have sucked up plenty of water/solution. I adjust it back up to 6.1-6.3 and let her go again until I have to top the water up

I tried using RW cubes but hated them. They were difficult to control the pH, and stayed way too wet for my liking. I stayed with coco and pearlite mix without any problems.

 

[surfinc]

i also rinse at week 4 roughly each time...
I asked for ideas based on history f running upwards in the resi tank...
that graph confused me more than anything...
You say you always drift down...im going on 10 months of drifting the opposite...everything is on par so....
So i keep an eye on it and move on...

 

[surfinc]

ive likened to the slabs but have had some success from 4 inch to pot with cubes... cost me 10 inches at the base so i abandoned ship and went to slabs..

 

[trillions of atoms]

^^^ or gunk n buildup in the rez

 

[Hushpuppy]

Multi IS correct about suddenly falling pH being root zone issues. I had that happen to me one time because I had fungus gnat infestation that I didn't notice until they had damaged the roots on one of my plants. The decomposing roots that had died were screwing up the pH and creating "gunk" in my rez.

Don't let my pH drift direction fool you as mine was specific to using the JJ with the coco coir. If yours has been rising since beginning of using your setup then suddenly changes, that means something is possibly wrong. Definitely keep an eye on it and look for other changes in the plants. If you can, check out the root zone and see what they look like.

 

[surfinc]

i wouldnt say sudden change...more like first tray out of last like 8 or so...same starins same feed...
I will look into the rooot zone.. Ive got 20 days left all looks good... i just hadnt had this drift before so wanted to learn... Thanks for the input..