Red Sea No3Pox4 or whatever it called. Feeds your bacteria and your skimmer starts producing more. I have been on 0 Nitrates for a while so just use to control occasional bit of phosphate periodically. I did use Aqua Medics Antired for a Cyano out break a few months back which worked well and followed instructions to the letter and had no negative impact on any corals.
Coral food, I tend to mix up a bit of reef roids with a frozen cube of rotifers. Suck em up in a syringe, turn off wavemakers, target at my corals with syringe. I let that sit for 10 minutes or so then crank wave makers. Just don't over do amount or frequency or you will have cyano and bubble algae all over your rocks. I do it once, sometimes twice a week. I try to do it day before I plan to do a water change.