What causes ph to rise

[dirwin85]

What causes my PH to rise? a lot of times i will adjust it then come back in a few hours to find it near the level it was previously at or way higher. sometimes it will stay stable for a few days and then go bonkers on me, thanks for your help as always

check out my grow
Bubblegum Deep Water Culture LED/CFL Grow!

 

[Lemon Paradise]

I am still a bit new,, but my understanding is that,, as the plants take up nutrients or take up water and leave nutes behind,, the salt concentration changes as the plants use different stuff,, and that causes the PH to change...

basically, you set ph after adding the nutes,, so nutes/water = desired ph,, and put in your res or soil,,,

as the plant drinks it up, that balance you just created changes,, as does the PH level..

I have read in the bubble forums (I am a soil grower) that after setting their res at the beg of the week,, it will slowly go up as the nutes are taken in... but to not adjust it more than once a day,, cause you don't want to f with it too much,, and a little drift is good, since some nutes get taken in better at different PH,,,,

hopefully I am somewhat on-base..lol and not telling you wrong,, others will be by ..

 

[PitViper]

I am still a bit new,, but my understanding is that,, as the plants take up nutrients or take up water and leave nutes behind,, the salt concentration changes as the plants use different stuff,, and that causes the PH to change...

basically, you set ph after adding the nutes,, so nutes/water = desired ph,, and put in your res or soil,,,

as the plant drinks it up, that balance you just created changes,, as does the PH level..

I have read in the bubble forums (I am a soil grower) that after setting their res at the beg of the week,, it will slowly go up as the nutes are taken in... but to not adjust it more than once a day,, cause you don't want to f with it too much,, and a little drift is good, since some nutes get taken in better at different PH,,,,

hopefully I am somewhat on-base..lol and not telling you wrong,, others will be by ..

reps
good answer.....
Im curious as to the size and amounts of the plants vs the resovoir size

 

[Lemon Paradise]

Thanks Pit,, I am glad I was not steering Dirwin worng..

and Dirwin,, not that Pit is on the scene,, you are in good hands,,,

this is a quote from ------- on the subject,, with charts and stuff... I love charts..lol

I had THREE new and different growers have problems with SPOTS on their leaves this week. Upon looking at some charts and comparison pics, they all needed the Botonicare Supplement CAL-MAG. They all had deficiencies.
But when I looked further, they all 3 were keeping the pH at 6.0 and lower, as often or as much as they possible can.

Look at these charts, both show HYDRO and SOIL ph levels that nutrients are digested.
You might want to book mark this page, many new growers have this same problem.....and often too.

In this chart, Hydro is on the left:

and here, Hydro is on the right:

Note that above a pH of 6.0 is where the CAL and Mag and Pot and Nitrogen are most digested or absorbed, especially the CA and Mag. To absorb ALL nutes, the pH should be allowed to flucuate up and down to get all the nutes. if you do not understand the chart, then ask. THIS IS IMPORTANT FOR RAPID HEALTHY GROWTH!

 

[dirwin85]

Thanks guys

 

[dirwin85]

what frustrates me is ill put in PH down then test it and i will be below or right on where i want then i come back in a few hours and i am right where i started or just a smidge below it

i am using powdered ph up/down... maybe i should switch to a liquid?

 

[Lemon Paradise]

.....
Im curious as to the size and amounts of the plants vs the resovoir size

so...? I am not a hydro guy,, but if Pit asked,, there is a good reason,,,

 

[dirwin85]

2 plants in a 6 gallon rez

 

[PitViper]

sweet setup....clean.
define how much it changes and how quickly.
your plants are healthy and look great..growing quickly Id say. its normal for a PH swing after a few days...but how much is what I want to know

 

[dirwin85]

ill dip a cup into the water to take it out to be able to mix it
this morning when i got up and checked it my ph was 6.75 i want around 5.5 so i put some ph down in mixed it up now its at 4.5 but within 3 hours it will be up around 6 again

 

[w4nn13]

dirwin85 looks like a space lab lol, I am new to this growing but I bought a hydro and my plant was 18in in size by fourth week and like a noob I did not top it an it is now over 7 ft grown way past my lamp and is hard to tie down.

Regarding PH level I don't have a ph tester only a strip of papar tester and when ever I use it it always looks same not very good but then again I not really had any problems the odd leaf tip and the odd yellow streak but other than that most of my plant looks great but yes I must get a good tester.

 

[dirwin85]

Thanks guys, i am about 1 month in from seed

Paper strips are garbage, if your running any form of hydro a pen is essential. I started with strips thinking i was right on and would be 3-5 points off.

My theory is that right when you put the ph in it shocks it so to speak and drops lower then after it circulates the tank and interacts with the nutes it levels off at a place similar to before the ph adjustment. so lets say i was at 6.75 i put in enough with the goal of reaching 5.75 it would hit that number right when i put it in and then slowly rise up to mid/upper 6's.

I am going to make a run to the local hydro store and get some liquid PH adjuster the powder doenst seem to stable (how is it dissolving, where is the resolved crap going, ect) and then maybe with a liquid i can get precise measurements on how much to add?

am i rationally thinking here?

oh and by the way how do you change your signature?

 

[ol hippy]

Ph should go up from when you start . My problem is the ppm doesn't go down meaning their not eating but the water goes down by a gal ! So I add back plain PHd water (5.7) and in 24 hours the ph may be 6.2 but the ppm is almost the same !? I'm due for a res change in a day or so , do you think that when I change the res and start with clean new nuted water this will change ?

 

[ol hippy]

When you add water (nuted or not) you shouldn't try to drop the ph too much at once ! If I'm not mistaken that can cause problems as well .

 

[dirwin85]

i think by the PPM staying the same with the water level droping they are drinking and using the nutes, think about how much higher it would be by just removing a gallon of water with same nutes. (IE adding a gallon to lower concentration)

 

[dirwin85]

It was at 5.5 when i left around 11, i came back at 1 and it was at 7.... wtf

 

[w4nn13]

Paper strips are garbage, if your running any form of hydro a pen is essential. I started with strips thinking i was right on and would be 3-5 points off.

Yes I must get a pH pen tester when I do my second grow I will have more money spend on it due to the fact I wont be spending any money for a while

 

[ol hippy]

dirwin, hows you water temp ?

 

[dirwin85]

74

 

[ol hippy]

Try to get it below 70 !! If your roots are in the water take the pump and drip lines out that helps too. I usually add cold water during the day or even take out a gallon add ice and put it back . The high temps can cause lots of problems ! Also if your using tap water check your ppm before you do anything , mine was 579 ppm so I use distilled from the store (about a buck a gallon).. you should get things back on track in a day or so ...