I've moved this to the Newbie section as you should get a better response here.
You should clean your filter from anywhere between once per week to once per month or so depending on fish load, feeding etc. I'd suggest cleaning it whenever you do a water change, ideally once a week.
It is very important that you use old aquarium water to clean the filter media (probably sponges). Tap water generally contains harmful chlorine/chloramine that will kill the beneficial bacteria that performs the biological filtration.
I'm unaware of the model you refer to but I assume it will have an impellar that will need regular cleaning too. An old toothbrush is ideal.
