Shoot!, That sure looks like it needs investigation. But, as it stands, I haven't noticed any slowdowns yet (not that I started with the fastest growing coral, because of no extra feeding) Maybe all my stuff has already been slowed down or maybe that isn't the whole story in a nutshell, like certain plants put out certain chemicals that harm coral while others don't.
I don't buy into any cart blanche concepts anymore, because nothing is so cut and dried in our reefs, but if algae is going to cause problems, I'm setting myself up for a doozy!
(maybe not so funny) My whole system will be the algae scrubber. (macros in every tank that can support them except the SPS tank,because the Mithrax crabs will waste anything soft I put in there) I have two tanks(well one tank and one sump) with the macros dominant and I am working on the other two tanks that can support it.
The trick will be deciding how much and when to harvest it, but now I am just growing it out.