I found that PE increased when I added a couple of tunze 6060s to my tank (previously using MJ1200s and/or Hagen 802s). PE increased even more (I hadn't known it could) when I added a wavebox
I do have a couple corals that have hardly any PE during the day but they're incredible looking at night. I usually try to feed reef roids or something like that a couple hours after the lights go out, or a couple hours before they come on in the morning.