Check out ACI aquaculture. The whole farm is ran off of kalk that is added based on pH. There are more than you think using this principle outside of reef2reef. I use a hybrid system of 2 part and kalk. My kalk is controlled to come on when pH drops below 8.3. I do have the limit set for max daily evaporation.Also @Sisterlimonpot has some great ideas. I just want to clarify that I believe he doses well above the evaporation limit and is able to do so with some custom made gadgetry and super salinity solution to keep salinity in check. Just to clarify this point for those that don’t know. It’s how he can target a specific ph. I don’t know of any one else that is doing this. Targeting a specific ph may require more than a basic kalk reactor on most systems depending on demand, evaporation and such.