OK, thanks. Another thing that impacts alk with a high alk mix is how much, if any, calcium carbonate has precipitated and settled out before the measurement. In my case, where I let sometimes IO sit for a long time on its old precipitated solids (which can act as seed crystals for more precipitaiton), I often got much lower alk. One study I did for other purposes showed the alk in the barrel was 7 dKH.
Do you know at what alkalinity level precipitation like that is most likely to occur? Assuming 74° or so and a power head going.
I just kind of say “high alkalinity salt” but I’d guess my definition of high alkalinity is just opinion and I’d say anything over 10dkh falls into that category for me. I just don’t recall seeing many salts under that level having the precipitation issues