The Nexus filter is a primary settlement vortex clarifier that flows through a special filter block before entering the biofilter. Easy to install; pump to or gravity feed it. The filter block is high-grade foam media.
The biofilter utilizes the Kaldnes moving bed process and Kaldnes K1 media, one of the most efficient forms of biofiltration. Polyethylene K1 media has a large surface area for microorganisms that remove ammonia and nitrite to attach. An air pump (not included) continuously circulates the elements while oxygenating water and stripping CO2. Its self-cleaning action removes the older, less active bacterial layer. Rated conservatively at 1.1 lbs of feed per 3.5 cu.ft. of K1 media; however, K1 media can handle up to 4 times that amount.
Measures 34" in diameter (50" W at inlet/outlet) and 33" H. It has a 4" inlet/outlet and independent drain valves for the sludge filter and biofilter. Includes 1.75 cu.ft. of Kaldnes K1 media and all valves and fittings. The biofilter chamber requires an air pump, so we recommend using the Sweetwater® SL56 air pump.