CPF-2500S/2500J Series Pond Bio Press Filter Description: This filter integrates mechanical and biological filtration (type A filter contains uv lamp). Maximum working pressure 4 meters. Convenient cleaning way, first open the drain valve, then switch to drain icon, turn clean handle to clean filter sponges(applicable to S filter). The newest design make the filtrate area double of before, improve the filtrate effect and make the maintenance much longer at large.