I have always cycled every new tank I have set up.
I always use 1 or 2 catfish for the cycleing,in fact every one of my Bettas(except for the breeding tanks)have 1 catfish in them.
I just set up a divided 10 gallon,I took one sponge filter out of one of the breeding tanks I am not using-put it on one side and a new sponge filter on the other side,1 catfish on each side.
I will let this run for at least 2 weeks before I put a female HMPK in each side.
In my 55 community tank I run a cannister filter and a double sponge filter,I will change the filter floss every month,and about every 2 weeks I pull out the sponges and clean them,that way my biological filter is always running.
In the cannister I have the biological media also,gets cleaned when I change the filter pads.
Not saying this is the way it should be done,just the way I like to do it.
As for cleaning the gravel,I can only get to 1 or 3 spots in my gravel,plants,moss and plant roots get in the way!
I just take water out when I do water changes!