Thanks for the feedback Hoppy. Here
is where you can buy that sponge.
It is definitely not the disposable kind. You can use that for years. I have Filstar foampads for 3 years and just recently started to swap them with new ones. (When I wrote: <<filters for several weeks>> I meant: before you need to give it a good squeeze!)
Of course the little pumps with inlet screen will not work for this, you need one that has an inlet which can connect to a piece of pipe.