We have a 3600 gallon koi pond with a DIY 4 chamber filter with one vortex. Its a pumped fed filter system. Im planning on improving the filter system. Right now, it contains some brushes, some japanese matting and some gravel, the 4 chambers isnt full of filter media. Im planning on adding more japanese matting and some k1 media. My plan is, vortex then brushes in the first chamber. Japanese matting on the 2nd and 3rd chamber and a fluidized bed filter using k1 media for the last chamber then water returns to the pond. My concern is, is it ok that i put the fluidized bed filter in the last chamber or it should be after the brushes??
