New pool and chemical question

[KurtV]

Yes, that will lower your alkalinity permanently (or at least until something else, such as your fill water, changes it).

Are you having trouble keeping your pH down or with scaling?

[CanuckPool]

The pool is only 2 weeks old, so I am trying to get a handle on getting it in order. The pH seems to always creep higher and higher as the days go on, I suspect its the SWG driving it up as the pool guy said. It appeared my CYA was too low initally (1 week ago it was at 5ppm) so we are currently trying to bring it up with Stab. Its at 15ppm now. If my pH always wants to move up, will that mean my Alk will always want to move up? or once you get your alk down, will it stay down unless fill water has high Alk. I am finding it confusing as alk and pH are connected... somehow.

[KurtV]

I'm a little over my head here and Evan (Waterbear) will probably answer this more thoroughly and accurately, but here goes.

The alkalinity and pH are related and will move together somewhat but they're not the same thing. For our purposes here, alkalinity is a measure of the resistance of the water to pH change; higher alkalinity will make the pH more difficult to change and vice versa. It will move down a little when you add acid to lower the pH but not radically and it will rise a little as pH rises. When you use Ben's technique for lowering alkalinity, the alkalinity will drop along with the pH but it won't rise again with the pH (or at least not as much) because you're aerating the water and releasing some of the carbonate that was in the water into the air.

I think (that usually gets me into trouble) that with your high alkalinity your water will probably tend to an always rising pH. But, if you don't have to add large amounts of acid often to control the pH and you don't have scaling, you might want be able to live with your alk as it is. If you find that dealing with the high alk is a big hassle, use Ben's technique to lower it.

There are a bunch of fascinating threads concerning alkalinity and pH on the forum here if you really want to understand this stuff. Look especially for posts by chemgeek and waterbear.

[CanuckPool]

Thanks Kurt, what you said actually makes sense, even to a layman like me. Sometimes the experts explain it with too much tech jargon and I tend to get lost. I am going to try Ben's technique when I get home and I will let you now how it goes. So far we have been pretty happy with our pool, just getting to know how to maintain it is the key.

[KurtV]

Just keep reading here and you'll have a firm grasp on it in no time. If you haven't already read them, the sticky threads at the top of the chlorine and testing forums are a great primer.

[PatL34]

Waterbear basically said it in his first post, and with a SWCG, it necessary to add the muriatic acid as it now part of the SWCG operation. There is a thread I wrote explaining this, just do a search in the Chlorine Generators forum for "SWCG Operation". I have tried to keep it simple for the newbie SWCG pool owners.

http://www.poolforum.com/pf2/showthread.php?t=1226

Pat