Looking good. My opinion: if that green stuff looks like film instead of hairy/fuzz, don't do anything different. If you had live rock or even painted dry rock, you probably would have barely noticed any film algae on the rocks. If it is hairy/fuzzy, reduce your peak photo period by 25% since you have no corals and perhaps consider feeding a bit less. Otherwise, don't do anything else different--and prepare for the tank to start looking uglier (not that I think it looks anywhere near ugly right now---so you're going to have a shock if you think it's ugly now!).
Is there a window in the tank room that can remain uncovered? Or a lamp you could put on a timer? Just something to give them a steady visible light cycle even though the overhead lights are off. Just my $.02.
You can help it along by scraping coralline algae off frag plugs into your tank. Or if you're me, you can clean the plug and just toss it in the tank.


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