Aquaforest AF Lab PO4+ is a concentrated solution of pure phosphate designed to maintain balanced nutrient levels in marine reef aquariums. This supplement helps ensure that beneficial zooxanthellae algae, which live in symbiosis with corals, have sufficient phosphorus for healthy growth and survival. By adding 1 mL of AF PO4+ per 100 liters of water, you can increase the phosphate level by 0.01 mg/L (ppm), helping to prevent coral bleaching and inhibited growth while maintaining a balanced NO3 to PO4 ratio in your aquarium system.