what ph is reverse osmosis water?

[rr14]

anyone?

 

[BruceLeeroy]

in my experiences very low ppm water coming out of an RO setup tends to be acidic, usually 5.0-5.5. i always thought it would be neutral but that just never seemed to happen. it is also VERY touchy and will be adjusted with just the tiniest of nudges, which is why most people add nutes before PHing the water i believe

 

[radium-]

hey my pH comes out at 4.7 very low and 1ml of ph up will take 13 Gallons(roughly 50 litres) to 5.8.

 

[BruceLeeroy]

hey radium do you adjust your ph before or after adding nutes? if before, what nutes do you use and how does adding them change the ph?

 

[mace_ecam]

Normally RO water is from 5.5 to 7.0 pH, depending on how much CO2 is dissolved and pulling the pH down...

It took me a couple of days to accept the fact that radium's RO water is acidry (~4.7),...

You should be able to add the pH up first, then the nutes (unless you are using potassiumsilicate for pH up), but only if you know how much of it you need of course

 

[Magic Bean Grow]

RO water doesn't contain much of any dissolved minerals to buffer the pH. So the pH can vary wildly depending on what traces of minerals are in it.

I recommend adding the pH adjustment after mixing the nutes since they will buffer the pH in the final mixture.

If I recall correctly, a charcoal final filter (carbon block) can lower the pH, so ~4.7 pH is not all that strange.

-- MBG

 

[RuralRoute420]

.

.

add nutes, then ph

most nutes will drop your ph. i always have to add UP when adding nutes....it sucks.



what's that called when your nutes won't affect the PH? buffered? does buffered mean it will or won't affect the PH if this is correct?

 

[Guest]

7.5 out of the tap.... and 6.0 after being filtered with my RO unit.

RO water IS going to need Cal-Mag and that will further drop the PH.

 

[BigToke]

…………..hay I have a great idea rr14, take YOUR ph meter and test YOUR osmosis water and you tell us, how’s that sound?

 

[HYDRO KING]

yea

yea

7.5

 

[rr14]

damn, just checked my water (not mixed yet) and the ph is over 7. The ppm is about 24 or 25. That ph seems out of control. I'm going to have to start testing the ph on every batch of water I get. I buy it from a water store across the street.

 

[foaf]

It really doesnt matter what ph you ro water is, because it has so very little buffering capacity to it that anything at all that you add to it, or that you add it to will dominate the ph determination. It is totally unimportant with ppms of 24 for example. You could breath on the water for an hour and your co2 would change the ph.

 

[HYDRO KING]

huh

huh

man stop trippin on the water ph before you add nutrents rr14, trip on it after. I never seen anyone care this much?

 

[rr14]

well, the problem is that I'm dealing with crappy test equipment. I don't have an electronic meter yet so I'm using my aquarium stuff. You can't really test the water once the nutes are in there because it dyes the water and throws off the readings. I'm going to pick up an electronic test device tommorrow.

I bet you would care if your plants looked as crappy as mine!!

 

[James-Bong]

PH= 7.0

3 stage RO