Many people run their lights 24/7 over their chaeto, caulerpa, mangroves and also algae scrubbers who seem to report great results. I don't know if this would be advisable for some of the red macro's though. I've been running 16 on and 8 off so far with my scrubber but I'm thinking about bumping it up a bit. I started out at 12/12 but I'm seeing better growth now with the longer cycle.