[Taras1]

My understanding of the reactors is that you take the media out of the filter bag. Place the media between the two foam disks. DON'T press the media between the two foam filter disks. The media will sink to the bottom of the reactor. You adjust the water flow through the reactor so that the top 1/2" of media perculates in the reactor. You can go to Drs Foster and Smith -- they have a copy of the instructions. On the Phosban media container it says how many grams of material will treat a given volume for either 3 or 6 mos.