Yes this is my 29 gallon (my only tank). It has been up and running for 8-9 months. Today I cleaned the filter and did a 25% water change. I do a water change once a week and clean the filter once a month.
I have a Penguin 200 HOB filter. What I do to clean it is take it off the tank, put the bio-wheel, filter foam and ceramic beads in a bucket of tank water and wash them around to remove any debris, then take the filter body and impeller and rinse them in the sink.
Is my filter not big/"strong" enough for a 29 gallon tank with this many fish? I updated my signature for my number of fish.