For any of you that think that the ATS is the only reason why your display is algae free, put a sheet out of your ATS in your display and watch what happens. I would scrape it down first so that the filaments do not float around the tank and start growing in the branches of your corals.
That happened because the tank broke down the roids and the po4 from the water got bound to rock and sand, like it does. That would have happened even if you had no algae source. The ATS did not do this.
Each tank is different, of course, but in my few decades of growing and exporting macro, everything except the largest refuge (of any type) are better at maintaining than lowering po4. This is a good thing, IMO. If they were good at lowering, they would not stop until you had none detectable. I am talking export of 5 gallon buckets of hair, puffy turf, bryopsis (good fuge algae, actually, but needs introduced), chaeto, etc.
Harvesting macro is a huge death event. I used to take time and pick out mini brittle stars and other other creatures, but you can never get them all. I still feel bad, though. For a few years, I had a huge mysid colony in my 125g refuge with untold losses from them living in the algae.
