Phosphate gets a bad rap in the aquarium world. Hobbyists, have been sold on the idea that excess phosphate levels are the main cause of algae growth and that they should be stripped from the water column at all costs. This has led to the use of products like granular ferric oxide (GFO) and various additives and dosing methods to remove the organic compound. Unfortunately, this ideology is completely wrong. While algae is fueled by algae, so too is coral growth. Corals need phosphate to grow, to be healthy, and to have good coloration. It sounds a bit sacrilegious to say this, but it’s totally true, and the most successful reef aquaria have phosphate levels hovering well above what is normally considered acceptable.