u/Dloe22

I have a ~700 gallon metal stock tank pond with ~12 goldfish and plants. It has always had a high pH, like 8 or above, but my fish have been alive for years, they've bred, plants are healthy etc.

I built a 55 galon bog filter over the weekend and filled it mostly with 2-3" limestone (topped with LECA). I was concerned the limestone would raise the pH, but tried it anyway. I just did my first pH test after 4 days of the bog running and I *lowered* pH to around 7.8.

My theory is that added filtration and algae reduction did more to help than the limestone did to hurt. I know it's also possible that time of day or other subtle factors may have played a role. Any advice? Am I missing something?

Thanks!