Absolutely it is.....if you're lazy!! Typically sponges used as mech filtration are cleaned at maintainance time, mine get a thorough wash and rinse under a warm tap until the water runs clear. No time to clog in my set up.is it possible to have a clog from sponges that are too dense
And as i've already mentioned, any sponges used as your secondary tier bio media, AS LONG AS YOUR MECH SIDE IS EFFICIENT AT PARTICULATE REMOVAL, then these sponges will remain crud free for a long time. Mine get a quick rinse maybe once a year....IN TANK WATER.
It all boils down to maintainance.