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View Full Version : Quick PH question...but no probs YET


greentrich
10-07-2009, 11:49 PM
Hello everyone. Just a quick reference question: What does a lower PH runoff indicate?? My PH in is around 5.7-5.8. Just recently my runoff came down to around 5.4.

There are no signs of problems yet, but I test the runoff every watering and it's slowly coming down. Just a few weeks ago it was coming out 5.9-6.0 fyi.

The method chosen: coco perlite mix (botanicare readygro moisture formula), progrow, calmag, liquid karma, and an occasional small dose of peroxide. Am in week six right now...going through the transition. Water with nutes everyday at about 800-900 ppm this week. Handwatering to waste.

Any insight?

Thanks everyone
tinytoon
10-08-2009, 11:59 AM
does whatever you are using to read your PH compensate for change in temp? Has the temp of res changed along with change in PH?
greentrich
10-08-2009, 02:56 PM
not sure if it compensates for it or not. It's a hanna tester, and while it does read the temp, I have no idea if it compensates.
I cleaned and calibrated it this morning, gonna see what it reads tonight after I did a flush last night.

There is no res, I am handwatering from water mixed nightly. The water pretty much stays the same as room temp.
tinytoon
10-08-2009, 10:44 PM
kk that kills that thought :wtf:
greentrich
10-08-2009, 11:57 PM
kk that kills that thought

LOL...ya but it's the thought that counts TT. Thanks for the brainstorm...any other suggestions?
tinytoon
10-09-2009, 11:53 AM
I seem to remember reading somewhere that PH cnages as plants feed but cant remember if it goes up or down during the process
Rubberbubbler
10-09-2009, 12:33 PM
I seem to remember reading somewhere that PH cnages as plants feed but cant remember if it goes up or down during the process

You are right pH will rise with time as plants remove nutrients
tinytoon
10-09-2009, 10:18 PM
HA i knew i wasnt nuts :D
PigLet
11-11-2009, 08:42 AM
what happen if the PH goes down what does that mean?
DreadedHermie
11-11-2009, 09:37 AM
What is the ppm of your runoff?

I have always nuted and watered alternately in a product like that. If your plant is using lots of water but not using the ferts as fast, it'll "concentrate" the ferts right in the pot. Acidic ferts get to be stronger acids, at least all the ones I've ever used did...
PigLet
11-11-2009, 10:21 AM
1080 ppm in the res its hydro
DreadedHermie
11-12-2009, 10:38 AM
Sorry guys, my bad...:o

Piglet, my question was for the OP, greentrich. What I'm getting at is that unused nutes may be building up in the pots. That can cause the pH to drop as the nutes get more concentrated. If that's happening, though, the runoff water will be high ppm's...simple!:thumbsup:


This was actually kinda for you:

Acidic ferts get to be stronger acids because that's what happens as they become more concentrated. (It also happens in a hydro rez.) If you're feeding more nutes than the plant can use, it will use water faster than the nutes (duh) and the nutes get concentrated as you keep adding them at the same concentration.

If you add non-nuted water to the res and the ppm starts to "correct" itself, that's what might be happening. (The pH should correct itself a bit, too.)

But we shouldn't jack greentrich's thread. You should post a question in the hydro forum and the experts there can help you.

Greentrich, I haven't used that combination coir product so I don't know if you can "pretend it's hydro" like you can with straight coco. But I run coco as low as pH 5.2, no problem. :thumbsup:


an occasional small dose of peroxide
Why are you adding peroxide? You know the pH is < 4, right?

Hermie