Nothing opposing or objectional here...
But although like you said, there are algae in the ocean and it's unavoidable as its a part of the ecosystem...
But there are also pockets of reefs in the world whereby the corals thrive in a low algae infestation environment, where delicate corals like SPS grow in relatively low nutrient and low algae waters.... this is wat I'm trying to replicate my reef to be...
After all, we all try to replicate the ocean dun we?