Is it though? Alkalinity sure, but why is it necessary to test Ca and Mg, twice daily, everyday. I run a SPS dominant mixed reef and find myself testing Ca like once a month, and Mg even less than that (and for what it’s worth, have never had a “bad” reading in either). And even IF you did have a Ca or Mg “swing”, it’s not nearly as concerning as an Alk swing. It just seems those two are better suited to manually testing much less frequently rather than burning resources continuously testing simply because you can.
I think Trident only makes sense for people who already have a full Apex set already (controller, couple DOS, etc), because you can add-on full alkalinity monitoring/control for $600. But for those that don’t, paying more than double that, if all you’re really after is the monitoring/control, just doesn’t make as much sense when compared to the other options. Apex should have considered making a stand-alone alk monitor, like every other competitor in the market did, if they wanted to break into the population of currently non-Apex using hobbyists. Instead they made a product suited for Neptune fans, which isn’t a bad thing of course as that is also a large population, and released it in a fashion to ensure it remains in demand for quite awhile.
The alkatronic seemed great right up until you mentioned issues with noise. That would probably be a dealbreaker in my house so I’m hoping the other options out there aren’t all as loud.