I have some pretty old base rock and some 15yr. old Florida rock. Seems as ongoing battle to keep algae from growing on it, despite high flow, bare bottom, 32in. beckett skimmer and ATS.
Mike Miles also had the same ongoing problem, in his 180 softy tank. I suggested, after all the reads on RC, that he try some Phosban. Remember he has been fighting with this algae for a year or more. After a couple of months of Phosban use, his algae problem seems to be gone.
Is it directly related to the Phosban? Who knows? He did add some calerpa to his sump, which is helping, I assume so, but he was running my scrubber previous, when I had no large tank.
So I decided my tank would be a good test. No other changes were made. But before I ordered Phosban, Phil at Xenia North America {Giesemann Lighting}, asked me if I would try some Rowaphos in my tank. Good test situation we figured. It arrived a few days ago. I started out with half the suggested dose for now. Been only a couple days so far. I will make a full report once I see some results, positive or negative.