API Phos-Zorb Filter MediaAPI Phos-Zorb is a filter pouch that specifically targets phosphate and silicate — two nutrients that, in excess, drive algae growth and the "diatom" brown film common in new tanks. When you're fighting an algae problem fueled by high phosphate (often from tap water or heavy feeding), Phos-Zorb removes it at the source, taking away one of algae's main food supplies.A Gentle Word of Caution — mind your plants: Phosphate is also an essential plant nutrient, so in a planted aquascape, aggressively stripping it out with Phos-Zorb can cause phosphorus-deficiency in your plants (stunted, dark, pinholed growth). In a planted tank the goal is usually to balance phosphate, not eliminate it. Phos-Zorb is most appropriate for fish-only tanks with an algae problem; in a planted tank, use it cautiously and watch your plants.Good to Know: Phos-Zorb is distinct from the nitrogen-removing Nitra-Zorb and the general-purpose Bio-Chem Zorb — it's the phosphate/silicate specialist. A phosphate test kit helps you confirm a high reading before using it and avoid overshooting.How to Use: Rinse and place in the filter's flow path after mechanical media. Replace when it stops lowering your phosphate readings; pair it with the underlying fixes (less feeding, more water changes) for lasting algae control.
