After I feed my fish at night around 5-7pm depending on the day. I let the fishies eat all the free food in the water column and at this point my return pump is off and my power heads are in feed mode. Once they are done eating I turn off my powerheads and target feed my zoas (and a couple others). Let sit for another 5-10 minutes then turn everything back on.
I'm always looking for more efficient and better ways of doing things though so i'm interested in how other people feed.