sequence is blurry

[gc]

I've been having trouble reading my sequencing gels because the
bands tend to get blurry after about 60-100 bases from the bottom
and I can't tell if I'm looking at single bands or doublets.  I've 
been running 5% acrylamide gels at 35-40 watts.  The buffer is 
1xTBE, except that I add sodium acetate to 1M in the bottom buffer
after the gel has run about half way.  Any suggestions on sharpening 
my bands would be grealy appreciated.

--gc
TheRoadToNowhere
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