Somerville Water problems?

[Piscevore]

The water coming out of my RO/DI is really HIGH ph. 8.75-9.0

I found this out because my tank ph has been super high. Which was freaking me out. At first I thought it was my meter's probe, so I soaked it in some vinegar. Cleaned all the coralline off, measured around 2.8-3, which seemed right. (This probe is not that old, from the group buy)

However, while rinsing out the vinegar from the glass with tap water, my ph spiked up to 9! This is my regular tap water--- at a ph of 9! Immediately I realized the issue with the tap water would also be the case with my RO unit, and it is coming out high from that also.

Is this something seasonal? Something bad? Any somervillians experiencing something similiar?
Is 9.0 an acceptable PH for drinking water?

 

[reefnroll]

If I lived in Somerville, I'd tell you that the pH of our tap water is always that high, but since I don't (according to Mr. Ryan P. Somerville)....



b

 

[PenMan]

Check a small batch of salt mix for the PH, some meters have a problem with RODI water.

 

[nunofs]

Tap water (at least around this area) tipically has very high pH to prevent pipe corrosion and heavy metals leaching into the water (namely lead). If you aereate it (to get more ambient CO2 dissolved in the water) the pH will drop over time.

Nuno

 

[nunofs]

And btw, see my comments on this other thread about the pH of RODI water: http://216.235.242.50/forums/showthread.php?p=58001#post57772

 

[Moe_K]

I once started a very similar thread over on the old RC forum.
Randy finally clued me in that our pH monitors are made for salt water, not fresh, and that he wasn't surprised I was getting a (erroneous) measurement of over 9.
Try using a freshwater pH test kit and see what you get.

 

[nunofs]

Moe, I'm not sure if this is the case here... the pH test kit I have is good for both FW and SW and it reads a very high value for tap water (don't remember how high, but IIRC it's 8.6 or so)... also, I've been researching pH monitors/controllers because I wanted to get one for my FW tank (CO2 injection) and most say that they're good for both FW and SW. Maybe Randy can clarify the issue for us.

Nuno

 

[Piscevore]

I mixed a 5 gal bucket of salt water for a change. I dumped in salt, dumped in RO, stirred a touch, and even after a few hours it was pretty high.

Thanks Bec
In -MEDFORD- I always noticed the Ph of the water was around 8.3-8.4, but not usually up near 9. My tank was spiking around 8.65 the other day and I was just not happy with that. Its this damn somerville water.
Thanks for the response guys.

 

[Randy Holmes-Farley]

All MWRA water is high in pH to reduce the corrosion of pipes, and thereby reduce copper and lead in the water.

The issue with pH meters has to do with purified water, such as RO/DI water, were neither a kit nor a meter is going to give accurate readings.

 

[Randy Holmes-Farley]

FWIW, if your tank water is up to pH 8.65, it is likely due to measurement error, inadequate aeration, or high pH alkalinity additives. The RO top off water is not the issue. Many of us top off with pH 12.5 limewater and do not reach a pH of 8.6.

How do you supplement alkalinity?

 

[Matt L.]

If you let pure (RO/DI?) water sit for a while, and possibly get some aeration/surface movement, then the pH will be close to 5.65, not an even 7, even though a pH of 7 is neutral and the pH of pure water. The reason the pH is 5.65 and not 7 is because of atmospheric carbon dioxide (CO2) being in equilibrium with dissolved carbon dioxide species in water. So first, the belief that the RO/DI water added to your system should be an even and neutral seven is slightly incorrect.

Then, we have to factor into account your RO/DI water, which like all of our water, is not complketely pure. There are additives the MWRI places in the water that the RO/DI filter cannot remove, so the pH will again be different from 7 (really 5.65).

Finally, as Dr. Randy mentions, pH meters have a very difficult time measuring neutral values, or close to neutral pH values, in dilute solutions because of the way they work. pH meters work best with solutions that either have some species dissolved in them (not RO/DI water), or at pH values away from neutral (which of course have species dissolved in them to make them acidic or basic).

Matt

 

[Piscevore]

I do dose...with RHF 2 part additive I haven't increased the amount I dose, but i was getting to the bottom of a bottle. I reduced my dosage of that a few days before, and I shook up the bottle and mixed it with a fresh batch. The PH wasn't going down too much at that point(but I was being gradual...i didn't want it to plummet!). I've been aerating my RO, I did 3 staged 3 gallon changes, and I cleaned the PH meter, and the PH reading did go down to around 8.3, which is more what I am used to.

Still, very harrowing. I'm now convincing myself it was never as high as it looked, but I'm not sure......still everything looks happier now. My Caluastrea Furcata always tells me if my water sucks....

I think this was a 3 part error on my part. 1) Dirty probe. 2) Too much Alk mixture 3) panick induced by the very high ph of my tap water.

For what it is worth, I called the water company, and they state our Tap water ph will go as high as 9.3, and that 9 was not an uncommon reading.The people from the water co are not very smart, too.