Don't know your pond setup... If your pond is new it has to cycle, just like any new aquarium but on an obviously larger scale. Biofilters are meant to NOT be cleaned. That's where the biological conversion takes place. Only mechanical filters should be cleaned - they're the ones that catch the debris to (hopefully) prevent it from getting into your pump and becoming debris puree and then clogging your bio filter. If you only have one filter it will take significantly longer for your pond to cycle as the bio-mass (beneficial bacteria - looks like firm jello slime) can't grow when you're constantly cleaning it off along with debris.

Not a big proponent of water changes myself. We have a five year old pond - water has never been changed. So many times people post "I just did a water change and then...". Maybe a coincidence, but it seems to happen all the time.

How old is your pond? How many fish, what kind and how big?