High PH and Low Alkalinity?

[Neo Seeker]

Hi, I'm new to the forum! :) I have a new pool and I'm a little confused about this issue. I had my water tested today and was told I had a high PH, but had low alkalinity. I always thought that water was either alkaline or acid? High PH= alkaline and by direction of the pool company I have been adding muratic acid to bring the PH down. Today my PH was 8.2, but at the same time the water alkalinity was low? Is there a simple explanation for this or a good link? thanks!

-Dave P.

[PoolDoc]

In water treatment, pH and alkalinity are related but different.

The easiest way to think about it is to consider alkalinity to be a particular water solution's resistance to pH change. If you imagine pH to be the position of a see-saw, then alkalinity measures how stiff the see-saw's pivot is. If the pH 'see-saw' is very hard to move, then the 'alkalinity' is high, and so on.

It gets complicated however, because the principle source of alkalinity in pools is carbon dioxide, as baking soda (sodium bicarbonate or alkalinity increaser) or washing soda (sodium carbonate, soda ash, or pH Up). Having a gas that can leave the pool, but affects the chemistry till it does, makes things confusing.

Lower your pH.

If you still have a problem, come back and we'll explain more. Or read this page, for some further explanation:

lowering-swimming-pool-alkalinity-step-by-step.html (http://www.poolsolutions.com/gd/lowering-swimming-pool-alkalinity-step-by-step.html)

[paigemetoo]

How do I raise my Alkalinity without raising my ph? My alkalinity is 75 and my ph is 8. I want to add baking soda but wont that raise my ph?

[PoolDoc]

You have reported having a vinyl pool.

Don't worry about your TA yet. Make sure your chlorine, pH, and CYA (stabilizer) are right. THEN, check your calcium hardness and alkalinity. Unless they are too high, or unless you are having trouble with your pH bouncing around, neither are that important in a vinyl pool.

[paigemetoo]

I have sodium bisulfate should I use that to lower my ph? My ph was good at 7.6 but because my TA was only at 60 I added 3 pounds of baking soda. Also should I be worried about my phosphate level and iron? my phosphate it is 300 ppb and my iron is at .4 ppm. I only know this because i had to buy cya because mine was not reading any with my taylor test kit so I had the pool store see if they could get a reading they got one of 20. The,y of course, wanted to sell me stuff to take care my phosphate level and iron but I am scared to do anything without talking to you guys/gals on here. My pool was a nightmare when I was listening to the pool store.

Thanks for ur help!

[PoolDoc]

Yes, use the sodium bisulfate you have, until your pH is around 7.2, or until you run out.

Don't worry about the phosphates, but that level of iron can cause brown or orange stains. The stains don't bother everyone to the same degree, and they are not harmful in the slightest to people. But, until I know what you want to do about the iron, I'd rather have the pH low, which reduces the chance of staining.