Ok, good choice. So as long as you have a completely covered top (1/4" mesh works great), you could do a few fairy or flasher wrasses. I would do individual species vs. trying to do a harem, as they are almost guaranteed to all turn male. Otherwise, anthias would be another option as long as you feed enough. The first ones that come to mind are Dispar or Ignitus. However I'm not an expert on them by any means, so I will let others chime in.
Sent from my XT1565 using Tapatalk