Welcome to Tropical Fish Keeping.
I agree with what other members have posted. Rinse the filter media as needed--depending upon how dirty it gets, this can be every week during the partial water change, or every other week, or once a month, etc. You want the water to be able to flow through the media which means it can't be allowed to clog up. Rinse the media in a pail of tank water siphoned out at the water change, as tap water with chlorine/chloramine will kill the bacteria that have colonized the media.