The Poly Bio-Marine Kold Ster-il Replacement Media Set is designed to provide superior water filtration for saltwater aquariums by removing contaminants and improving water quality. This set includes a 0.50 micron bonded carbon block with molecular sieve, which effectively absorbs heavy metals, volatile organic chemicals, and phosphates while maintaining a flow rate of up to four gallons per minute. Additionally, the Fin-L-Filter bag filter removes harmful microorganisms such as algae cysts, Giardia Cysts, Cryptosporidium, fungus, and E. coli bacteria, ensuring water safety for marine life.