Peat & pH

I am trying to lower the pH of my tap water naturally. As it comes from the
tap the pH is 9.3, if I let it sit for about a month aerating it several
hours a day it will drop to 8.1, which is rather confusing to me. Can anyone
explain this to me?

I want to make peat water and mix it with the tap water to lower the pH. I
prefer not to use straight peat water because of the color, I would prefer
water of a rather clear quality. In straight peat water what is the lowest
pH that I can expect? Does the amount of peat have an effect on this.

At present I have a Fluval 403 filtering water in a 30g trash can. The
bottom 2 containers have a layer of filter floss in the bottom then filled
with peat. The top container has the regular Fluval foam filter to help keep
the small particles from getting in to the trash can. After about 2 hours of
operation the pH dropped to 6.64 but this morning the pH was 6.98. The KH
had went from 3.8 to 1. After the carbonate buffers are depleted will the pH
start to drop again?

If I mix water with a pH of 8.0 with water that has a pH of 7.0 will I get
water with a pH of 7.5?

Once I get the pH down to where I would like it to be which is around 6.8 if
I add carbonate buffers back into the water will the pH go back up?
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        | Allen Sandifer              |                     
        | ibi007 at mail_connect.more.net|                                
        | ST.Louis, MO                |
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