By tile do you mean like ceramic or somethingOh could probably put something on the filter. A piece of tile on where the water comes out so that it trickles over.
What type of sponge? Kitchen sponge that’s brand new? What’s the negative of reducing surface flow and could that be fixed by a bubbler or air stoneWith my aquaclear I suspended some coarse sponge where the outflow meets the water, this completely breaks the flow and reduces the number of bubbles immensely as the water diffuses through the sponge. It does reduce surface flow though.
Where can I get it at?