I bought Arm and Hammer All Natural Super Washing Soda.....is this the correct stuff that can be used to raise pH .

Thanks

Also called soda ash. Yes it can be used, and it will also raise your TA. If you don't need a rise in TA, then use borax.

It depends on what your TA is. If you need to increase your alkalinity quite a bit, then it could work well for you. If your TA is only slightly low, you might consider the 20 mule team borax powder as it increases Ph while increasing TA much less. If your TA is already right where you want it, you should aerate to increase Ph.

Play around with the "Effects of adding chemicals" in http://www.thepoolcalculator.com to see how much TA you would add with each of the chemicals. Just make sure you plug in all of your numbers correctly first.

Agreed ... the pool calculator is like Garmin for your pool. You want to get somewhere, raise your pH ... the pool calculator is going to tell you how to get there AND tell you what the effects of adding chemicals will do to levels of other chemicals along the way. As both above posters suggested, be aware of your TA level when you need to raise pH. I have a high TA so I do one, two, or a combination of both to raise pH ...1) Aerate and 2) Borax (increases pH without increasing TA as much as Soda Ash)

So If I aerate by turning on the waterfall and fountain, how much of a rise would I see in the course of a day. Or is aerating something that takes days and days?

I think there are too many factors to make a guess. In my pool, I have experienced decent changes within 24 hours using a homemade aerator similar to this post http://www.troublefreepool.com/my-diy-aerator-t21867.html#p180448

With a waterfall and a fountain, I would check the Ph after 4 hours to see. Also, I recall reading that you will see a faster rise on the low end of the scale than the higher end (going from 6.8 to 7.0 much faster than going from 7.4 to 7.6).

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So If I aerate by turning on the waterfall and fountain, how much of a rise would I see in the course of a day. Or is aerating something that takes days and days?[/quote]

I can't tell you exactly and I don't think there is an exact science here, but in my usage of aeration (one eyeball return turned up for approx 6hours) I have seen my pH rise from 7.2ish to 7.4ish. Remember, we're looking at colors here, not actual number data. But the shade of red DID change towards the 7.5 range.