Good point here, we all should know here the quality of our tank is greater than the sum of its parts. It is the combination of everything we add to the eco system.
No single one thing is going to be the silver bullet for anything.
Actually, in one case it was the silver bullet. I had a tank that got no algae through the entire live of it except green water. I attribute this to it being by a window. I had a portable UV for awhile. Then I tried Purigen, thinking it wouldn't do anything. It got rid of the green water really fast. I never got green water again but sometimes I would notice that it had green spots.
That is an odd thing though. I have never had a tank that balanced get green water.