You've been really thorough with your tank. Its hard to come up with an explanation but, there are tons of reasons something can go wrong. I've seen personally in the past acros just dying for no reason. More often than not, its been subtle mistakes like extra dosing too close to an autodose schedule, having something in the water building up over time that we can't test for (my main purpose for doing water changes), something nipping at corals (despite you not seeing it, not like you watch it 24 hours), something stinging/eating corals at night at it moves around, or other corals secreting battle chemicals near others. Not all acros can be near other acros. Be sure nothing has long tentacles nearby and there aren't any night time hitch-hikers.
Have you changed anything else that you aren't remebering? Added any new fish or inverts? Dosing any trace elements, phyto, or aminos?
Hence the title - it may be that I simply have some acros that hate life in my tank. Things happens sometimes. SPS can be picky. I recognize that. This thread was to see if there was something aside from the obvious that Im missing, or if there is some kind of trend where certain corals dont respond well to method changes (which some dont, I would guess). My acros are well removed from other non-SPS corals, so I dont believe its something stinging them, plus it is wide spread throughout the tank. If the recessions/issues were localized, I could see that being a rogue chalice tentacle or something like that. And its not local to one species of acro - spaths, millies, and others are all effected.
The only thing that has been introduced to the tank in the month that Ive been running the system are 13 acro frags that were purchased at the same time (Bayer dipped, removed from original frag plugs, mounted on fresh plugs, dipped again, then added to a rack) and a mini-max anemone. Prior to that, I havent added any fish or other inverts since end of August. I am only dosing Base Elementz - no AcroPower, other aminos, phytoplankton, etc. I have more than enough going on without having to remember to add another splash of this or that!
Thanks for the comments. Hopefully its something that is either clandestine (acros just hate me) or some elemental build up that I dont test for. We'll see what the Triton test results say.
I would suggest that the Triton method, or at least the way you are using it is the problem.
You have a 366 gallon system including an algae refugium. Given your perceived stable acceptable parameters (assuming all sps relevant parameters are good) and appropriate lighting, you are left with whatever/however you are adding chemicals to the water as the culprit to the sps issues.
You didn't have issues before Triton but do now, coincidence ?
How did you maintain Alk, Cal etc previously?
I dont think its as simple as you make it sound. Others have had quite the success with Triton - my setup meets all of the parameters given by the method, and I have some corals that are responding quite well. These complex systems have more moving parts that most of us are aware of and while adding chemicals seems like a culprit, it would be no different than any other type of two part system.
Previous to starting the Triton method, I was dosing using BRS two part on an infrequent basis, along with water changes. With such low demand for calc/alk, there wasnt much that was needed to keep numbers stable. Upon starting the Triton Method, the uptake of calc/alk increased within a week, and to keep parameters stable, dosing was increased. Growth from many corals is an indicator that the method is, in fact, working - however some of the corals may not be taking to the change well.
Thanks for your comments and insight!
Double check, triple check, alk tests. Have another local reefer ( or fish store ) do a test to confirm your readings. Lower to 7dkh. Calibrate your salinity tests, double check and triple check that it is accurate. If salinity is actually 1.028-1.030 it will stress out acros but LPS etc. don't seem to mind as much.
With acros are loosing at tips and/or base and its relatively slow process, alk too high is the most common in my experience. Like others have said though, it may not be easy to identify that is one of the biggest challenges with acros.
I understand that need to confirm testing - I'm a research chemist by trade, so Im all too familar with titration testing and the like. My main testing is done via Hannah checker, and Ive used Red Sea and Salifert alk tests to confirm my numbers in the past. I actually was very concerned with this in the beginning (before making the switch to Triton) because it all hinges on starting your system at a dKH of 8. Ive also used three different reagents in testing, and have gotten the same (within 2 ppm) numbers on my tests, so replication confirms that the testing is on point. I calibrate my refractometer with 35ppt solution prior to every reading. Again, I dont believe these to be an issue, but thank you for your comments.
about it, and a little frustrated :mad:, but I think the realization that even taking things slow and going all in on a good method with stable parameters can still have some setbacks 
. Even people with amazing looking reefs (GlennF) that have changed over have had issues (which lends credence to the fact that some corals dont handle change well). One month isnt a lot of time, and in the grand scheme of things, the tanks only been set up for 8 months - so maybe Im still working on getting a matured system... who knows. I'll stick with what Im doing, keeping things going nice and slow with stable, well monitored parameters. Maybe someone else using this method will speak up to their experiences changing over from one method to another. 
As with my other tests, the results are consistent, which would lead me to believe that it is not an analyst error in testing, but a result that is beyond the precision of the instrument, when supplimentary evidence suggests that the phosphate is indeed present.
