High pH and low KH.
Hi, I have been searching for a cause of missing fish (herons, raccoons bullfrogs) and now come to the conclusion that it could be due to water quality issue. My pond is >5 years old, well planted, with a liner surrounded by field stone. My nitrites and nitrate levels have always been undetectable. However, the GH levels have been decreasing over the last few years (range 8 to about 4 degrees hardness now) and KH has always been relatively low (2-4 degrees). What I have finally noticed is that the pH levels change relatively drastically from a minimum of 7.5 to 9.0 over the course of weeks. I plan on testing pH throughout the day tomorrow (am to pm) to see if the changes are occuring rapidly (as I suspect). So I would like to see if I can increase the buffering capacity with either sodium bicarbonate or calcium carbonate, to reduce the pH fluctuations. Any thoughts on which would be better and if this could explain loss of fish (which I assume if they are stressed enough, die and then are consumed by the remaining fish, since we have never found body parts in or out of the pond). Any help is greatly appreciated!
Category: Ponds-Koi
