Kind of right, James. That's why ulns like zeovit or fauna system strive to have 0 PO4 and then use their prescribed food to control the sps growth and colour, without which they will bleach and die. And these systems usually keep very little fish do as to keep the nutrient down.
Personally, I like to keep many fishes, feed them well so that they shit well, and the sps live well. But the nutrient exporters must be there.
Cheers
YT
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