TallPine -
At 8.2 pH, and my advice based on lots of pro advice here on this forum is DO NOT use or add any more lime, limestone or crushed lime aggregate until you get your alkalinity under control. Your pH is good, you need really need to raise your alkalinity. What I was told and in the calculations above shoot high to 70-90ppm. So its just at the minimum after applying Gypsum.
Gypsum is the element that will do that, raise alkalinity and not raise pH, thats what I did in my pond, that had low but not REALLY low alkalinity like yours. In your first post you mentioned needing a buffer, thats exactly what alkalinity does for pH in a pond.
Best if luck, but it's not luck if you're lucky.
Last edited by Stressless; 04/14/23 12:10 PM.
