PH Problems

[Nitlion15]

Need some help from the more experienced members of the forum.  

I keep having to add PH increaser every week.  My alk is always o.k. or even a little on the high side.  I thought alk and PH tracked fairly close together.

Could the calcium hardness be too low.  I use dichlor and I also heard that if I keep the level too high, it may affect the PH.

Any thoughts would be appreciated.

[Vinny]

The PH can drift lower as you use the tub. Other things that can affect PH: MPS, dichlor (as you said) and the water itself.

PH is something that you need to look at and adjust ... sometinmes weekly.

[mxw128]

Interesting you posted this now as my PH just took a nose dive!  It's been pretty rock solid since I got the tub and haven't had to do much with it, but when I checked it this week it was off the scale low(along with Alk) ...  don't know what happend but I had to add quite a bit of PH up to get it back into the normal range.  

[tony]

Everything that goes into the water is going to affect pH, whether it be people, dogs, lotions, chems, etc.  Generally, MPS and bromine will draw ph down as both are low themselves.  Dichlor is so slightly acidic that it is considered neutral, but will also gradually draw pH down.  Bleach or lithium will raise pH.

PH should be checked weekly and adjusted as needed.

[ssbraun]

You'll see this elsewhere if you search, but it is important to get total alkalinity (TA) correct, and THEN correct PH.  Otherwise, PH is prone to swing up / down "wildly".  It is "normal" to require PH increaser periodically, as the dichlor (chlorine) will have a PH lower than the ideal range for your tub, and will cause it to drop over time.  I add PH increaser weekly, also.

[Vinny]

You'll see this elsewhere if you search, but it is important to get total alkalinity (TA) correct, and THEN correct PH.  Otherwise, PH is prone to swing up / down "wildly".  It is "normal" to require PH increaser periodically, as the dichlor (chlorine) will have a PH lower than the ideal range for your tub, and will cause it to drop over time.  I add PH increaser weekly, also.

I never worry about TA in my spa, I use baking soda in my spa and my PH stays "locked in" for a couple of weeks. I tend to get it to about 7.6 and it will drift down to about 7.0 in about 3 to 4 weeks. It doesn't swing wildly but I start out with water that's at a 6.8 PH so I do believe that my TA is raised accordingly while using the baking soda. If I remember correctly I think my TA from when I first got the tub ends up a little higher than the "TA Range" in the Taylor book ... which is why it stays pretty stable.

[ssbraun]

That is all well and good Vinny, but there is lots of info out there that points out that if TA is out to lunch, PH IS harder to control.  TA needs to be in the acceptable range (80-120 / 150 depending on what you read). If it is not, PH can be a frustrating battle.

[Vinny]

ssbraun,

I think the secret to MY water is the baking soda is raising both the PH and Alkalinity at the same time.

I think that anyone who starts out with low PH out of the tap should try baking soda, that is unless the alkalinity is already through the roof of the tap water.

My experience doesn't mean it's right for everybody but it could be right for somebody. And if the water is balanced for the most part what does higher alkalinity do, only things I can think of is possibly raise PH and possibly scale. I said possibly not definately, remember as the PH goes down so does the alkalinity (possibly alkalinity first).

Remember your experience with your water may not be right for everyone else either!

Vinny

[marks]

Just to to confuse the issue.  I have the opposite problem.  My PH increases every week.  I add some PH decreaser that I got with the tub.  On my first fill I had to drain the tub because I did not pay attention to PH.

[tony]

My TA ususally stays on the slightly low side, around 70-80.  My pH stays consistant with slight drifts usually down, sometimes up.  I always use baking soda to raise, never soda ash.

[ssbraun]

Remember your experience with your water may not be right for everyone else either!

Vinny

Vinny, I wasn't trying to be caustic (pun intended ) or preach "my methods"...I just wanted to relay very good info I learned on this site which has helped me immensely.  Your statement that you don't worry about TA applies to your situation.  However, if TA is out of range, I learned here that it should be brought into range BEFORE attempts are made to alter PH.  If PH is low and TA is low, then baking soda may do the trick.   If PH is high, and TA is low, baking soda will raise TA to an acceptable level without raising PH "much".  I have had plenty of experience with this as I used to have high PH issues due to the use of lithium hypochlorite.  Now that I use dichlor, ph drifts down a little over the course of a week (which I understand to be "normal").  This means I need to raise my ph a bit each week.  I use a PH up product, others use baking soda.  My point was to answer the original question about dropping PH (it's ok) and PH / TA sticking close together (not always).  

Steve

[Nitlion15]

Thanks for all of the helpful insight.  I am currently using strips and it sounds like I also need to get a Taylor kit to get a more accurate reading.  

Until then I think I will keep adjusting the PH up a little each week.

Where can I get a Taylor kit?

[Vinny]

Steve,

I apologize as I thought you were trying to be caustic.

I know through this and other forums - both pool and spa, that people get too hung up on the TA side and this is the least of people's problems IMO.

From what I've experienced and read, some people chase the ultimate in balanced water (myself included when I was a water care newbie) and they think that TA is very important and again IMO alkalinity should take a back seat to PH.

Something that I do find interesting after reading people's accounts of their tubs is that my PH doesn't drift down too sharply even when I hit the tub with MPS which has a PH of about 4. I guess it's true ... even though it's all H2O, water is different all over the world!

Vinny

[JJ]

I think TA is probably the most important thing in a spa.  That's why I have screens all around mine so that I can enjoy it more often.