Hard to pin down since there was quite a number of changes.
Flow. It went from a protected location in where it used to be (
BRS reef saver rock) to the base of the Y in the tonga rock.
Light. Light intensity has been increased since it's about 3" higher in the tank than it was before. Other than intensity, spectrum hasn't changed. I just run the Fiji light cycle on the Vegas color.
Additives/supplements. Just normal
BRS 3 part via doser. I've started on A/B again, but the colors were showing up before I started.
Nutrient levels. The tank bottoms out on nitrates and I was dosing KNO3 to get it to sit at 5 ppm. I stopped and just upped the number of fish in the tank which increased how much I fed them. I haven't measured nitrates in awhile though.
Oh, I should also mention that the period when it had the purples and yellows was right when I got back from the holidays. Tank was on autopilot for 2 weeks during the holidays and my doser ended up raising my alk up to 12.8 (from ~8ish). I lost a few frags from that, but the ssc didn't have any issues.