ATI ESSENTIALS SPS VS MIX

[Luna's Reef]

Hi all.
I have a question: why is the SPS version more diluted than the Mix Reef? My initial thought was that SPS should have more concentrated KH and Ca because it will feed SPS corals, the only possible reason that I think could be is that the SPS has more trace elements than the Mix reef. If anyone knows this will be great to know. Thank you.

 

[Gumbies R Us]

@Randy Holmes-Farley

 

[Randy Holmes-Farley]

Most two part systems are limited in concentration by the solubility of the alkalinity part, not by any functional issue.

The mixed reef contains some of its alk in an organic form (probably formate or acetate) and thus can be made more concentrated than the SPS version which is purely inorganic (likely carbonate). The lack of organic can allow a higher resulting tank pH.