I just finish completed my pond construction two weeks ago. At that time the pH reading was above 9. My dealer told me that is expected from a new pond as materials from the cement wall seeps into the water causing the rise.
He poured some vinegar and the pH came down to about 8. He says the vinegar will 'cure' the wall of the pond. Now two weeks later the pH is 8.8 and he ask me to pour in some more vinegar yesterday which i did. I am yet to do a pH test.
My question is "What does the vinegar actually do?" I know it is acid and obviously it will bring the pH down but isnt this just a temporary measure? I read some where that it is quite hard to change a pH of a pond because each pond is different and each has its own pH. Also the realy danger with pH as i know is drastic changes. If thats the case would it not be better to leave it at 8.8 or even 9 for that matter? The kois seem very active and healthy to me. However my dealer told me that one of his customer's koi died and when they check the pH it was 9.2. I am actually skeptical if it was the high pH alone that kills it or something else.
Please help enlighten me.