"~ jan JJsPond.us" wrote in message
...
On Fri, 18 Mar 2005 17:34:15 GMT, (~Roy~) wrote:

Why does your pond spike so high in PH..........

I have cement blocks around the edge, last year was the worst and they
were
5 years old by that time, acid washed many times too. Don't know what the
deal was. Lots of baking soda and water changes took care of it. ~ jan

Cement blocks like pavers or cinder blocks? I would have assumed that
anything underwater would have sealed over and anything above would have
aged sufficiently. Maybe the acid washing is keeping the blocks porous and
the leeching continues.