Pondmaster® 05410 CPF 250 Series Pressurized Filter 250 gal. The Pondmaster® CPF Series Pressurized Filters are ideal filtering systems for small to medium ponds and water features. They've been designed to reduce required maintenance while establishing a healthy environment for fish and aquatic plants. This integrated system can be conveniently located in or near a pond or patio container. The UV Clarifier models help clear ponds of green water algae.