Experiments with Peat Moss

In an attempt to lower the pH (and make fish and plants happy) in my 50 gl
planted tank with Cardinal and Red-eye tetra's, I am going to experiment
with my change-water. At the moment I have a pH of 8.2 and KH of 8 in the
tank. I am using a commercial "natural" Co2 system based on fermentation.
Clearly it is not doing as good as it should. I have been using it for a
while, but neglected to refill. I may swith to "pure" Co2, but have some
space limitations. I also recently increased the lighting to 110W 7500K. I
am using tap water. I have now setup a 32 gl Rubbermaid with 8 qts of
Sphagnum Peat Moss (100%), no fertilizers (I certainly hope) in a
pillowcase. The water is stirred by a powerhead and has already turned dark.
I plan to let it sit there for a week, then use it for waterchanges. I will
be tracking the pH along the way.

My question to the group is, have anyone tried similar thing? Are there any
pitfalls?

Any comments are appreciated.

Peter.