I have SPS and run between 250-500 PAR throughout my tank depending on placement and time of the day). I routinely do 10-15% WC weekly using IO regular. Still, my ICP tests revealed some low trace elements and Randy recommended Tropic Marin A and K (I don't recall exactly what was low). Within days I saw my blues and purples pop like never before.
The benefits of dosing trace elements to me were very clear. However, dosing A and K and not knowing the exact dosages of what they had IMO left me at risk for some elements being consumed faster than others, or said another way, may not have covered all the bases if my tank consumed elements in a different ratio than the A and K provided. If I was conservative and I dosed for the lowest element consumed I could essentially be under dosing something else. I guess I could have just continued with the A and K and just bought the traces elements that I found lagging and dosed them up to speed in addition to the A and K. Though it still left the issue of determining how much to raise the A and K not knowing exactly what I was dosing,
In hindsight, I'd have to do a cost analysis to see if that made sense. I was dosing A and K off the cuff really (about 5-10 Ml a day I think) and wanted something more objective. I also liked that Captiv8 can essentially all be mixed together for one (or at most 2) dosing cocktails (master dosing solution he calls it). I considered Reef Moonshines but needing to daily dose and having to do it all separately was a no go for me.
My master dosing solution is mixed for 40 days and I dose a precise amount daily (30mls I think) with all the trace elements combined based on ICP testing and consumption. He provides a spreadsheet where you enter your ICP values, your last dosing amounts and it re-calculates the new "Master dosing solution". Chris in general was very helpful. That said his analysis and spreadsheet are very robust and informative and I found I had a lot of questions. I wish there was a forum because after a while he wasn't really responding to my questions in a timely manner. To be fair to him, in hindsight the information I needed was there, I just was overwhelmed in trying to find it all and be confident I had it right,
All of that said, I just started 3 months ago and got off to rough start. I didn't have everything I needed to create the master dosing at the values recommended, I ran out of A and K (and didn;t want to buy more since I was moving away from it) so I didn't taper like I wanted to (and should have), and my IC test coincided with holidays and massively delayed my getting the results (required to determine the new master dosing solution - lesson learned and now I prep a 40 day master solution and test at 30 days. I also bought the Isol8 MT which is guesstimated blend I guess that can suffice in filling a gap in dosing your master solution)
In a way these bumps and gaps inversely validated what I originally saw. I know I was under dosing (having not had enough time or testing the compensate for stopping the A and K) and in rather short order I saw loss of color in my SPS. Particularly the blue and purple I gained after starting the A and K. I guess the real test will be down the road seeing if the Captiv8 dosing restores that blue and purple coloration and hopefully even surpasses it by popping other colors the A and K did not.
Sorry for being so long winded but I felt compelled to share what I have seen and experienced so far on my journey. Good luck on yours.
Speaking of the journey, it sounds like you may be rather new at this. If so, most likely getting stability in the big 3, your lighting and nutrients in order would be the best place start. Then consider the trace elements. The A and K did wonders for my tank (but it was well established and stable with good growth). It remains to be seen in the Captiv8 / ReefBlue print will equal and surpass it regarding my colors.
