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Does PH Up/Down go bad?

iSmokeTrees

iSmokeTrees

Member
I just used some PH down for the first time in awhile and it caused my PPMs to skyrocket. This never happened before. Why on earth would my ph down boost my ppms so much? I'm afraid it will kill my newly transplanted clones.

Thanks.
 
C

cashmunny

Member
iSmokeTrees said:
I just used some PH down for the first time in awhile and it caused my PPMs to skyrocket. This never happened before. Why on earth would my ph down boost my ppms so much? I'm afraid it will kill my newly transplanted clones.

Thanks.
Click to expand...

It won't go bad.

It increases your ppm because up is made with phosphoric acid and down with potassium hydroxide usually. So you are adding phosphorus and potassium in mineral salt form which raises your ppm.

I'n not sure if an organic acid like acetic or citric would raise your ppm. Not sure if ppm meters are sensitive to larger molecules.
 
E

EvilTwin

iSmokeTrees...
One thought...
How much did you have to correct? What I'm getting at is if you were using high ph water (tap) and meeded to use a lot of ph down...that might explain your rise in TDS.
ET
 
C

cashmunny

Member
If you are using tap water, the calcium carbonate in it acts as a buffer. So you need a lot more down to lower the pH than with RO water. And the phosphate ion from the acid will register on your ppm meter just like any phosphate ion would.
 
iSmokeTrees

iSmokeTrees

Member
Well I use RO water. In the past I never had a large ph spike when adding up/down. I am at a new location and my water is harder coming out of the tap and seems to be coming out at a higher ph subsequently after RO, so more ph down.
 
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EvilTwin

Hey iSmoke,
Even starting out with a higher TDS tap...running through an RO unit will still bring it down pretty low. So I doubt that's much of an issue.

Can you give us some numbers. An example...
What's your starting water, what happens when you add nutes (ppm) and finally how much ph down do you have to add to get it where you want?
ET
 
iSmokeTrees

iSmokeTrees

Member
Hard water has a higher PH too. I don't measure how much ph up/down I add, I just add, stir, wait, check, repeat if necessary.
 
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EvilTwin

Yes, but when you say the ph down makes your ppm go sky high...it would be useful to have numbers to know what you mean.
ET
 
iSmokeTrees

iSmokeTrees

Member
In the process of going from ph 8.something to 5.9 my ppms went from about 240 to 830. My RO water ppm is 10, I had about 50/50 botanicare calmag and progrow for 240.

Just transplanted clones, first week of veg, first time cloning, I'm worried the ppm is going to kill them.
 
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EvilTwin

iST,
Those are some dramatic numbers. I can't figure out why your RO water is ph 8 at 10 ppm. My tap water is 340ppm @ ph 8 and after going through the RO filter drops down to around 25ppm @ ph6.

I agree with you that something is very odd there. Just for an experiment...why don't you buy a few gallons of RO water ("drinking water" is ususally RO...don't want spring water) and see how water from a different source responds.

There's either a problem with your water or with your ph down to cause such a rise. Using so much ph down also doesn't leave any "room" for your nutrients either.

If there was a filter problem with your RO, you wouldn't get a reading of 10ppm on the output water.

Are your meters all quality and calibrated properly?

Just thinking aloud...
ET
 
C

cashmunny

Member
iSmokeTrees said:
Well I use RO water. In the past I never had a large ph spike when adding up/down. I am at a new location and my water is harder coming out of the tap and seems to be coming out at a higher ph subsequently after RO, so more ph down.
Click to expand...

That does sound strange.

I have some very hard water where I live, around 700 ppm. So RO membranes seem to go bad quickly. You could slice my water and have it on a sandwich for lunch.

Have you replaced your membrane and checked the calibration on your EC meter?
 
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