As long as
the pH is above 8.5 you can add lots of baking soda. ~ jan

Um....did you mean as long as the pH is below 8.5?

No, I meant above. As baking soda will only bring the pH to about 8.3-8.4,
it isn't going to drive it higher if you add a bunch at higher pH levels,
it will just improve the buffering.

So...not to be dumb but...do you mean you can't add baking soda when
the pH is below 8,5? Or just that you have to add it slowly so you
don't change the pH too fast?

Thanks for the response. I'm so glad to know your situation settled
down. My pond is about 3 years old this year too. Maybe it's the
"terrible threes"? Joan

Could be. How are your plants doing? That's how I can tell when my pH is
too high, the plant growth slows way down. ~ jan

Plants are doing well. The algae's doing great! :-P What do you
think about those peat granules that they sell for ponds? They're
supposed to tint the water slightly and gradually release humic acids.

Joan