The caustic potash will get the pH up, but it will not keep it up. You need
to get some carbonates and bicarbonates in the pond to stabilize the pH.
Regular old baking soda is the cheapest and quickest method of getting these
carbonates into the pond. Use about a cup in your pond and see if it
doesn't stabilize the pH. It will be higher than you currently have, but if
you dumped in 5 pounds, it would not raise the pH above 8.4, which is
acceptable.
--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html


Rich wrote in message ...
After hearing about PH changes I jumped.
I brought home a PH meter from work and tested my water.
500 Gal with a 5.4 PH at the start.
I also got from work Caustic potash flakes.
I added SMALL amount 6 - 8 flakes and took two tests.
I average 7.5 & 7.1 as water cycled through the pond.

That with my barley straw I hope to see less bottom grass soon.

Rich