I had the same issue when I switched to a cup. My return water was flowing over the cup because I had too much media in it. I switched my media and the water drops into the cup now and less dripping noise. It still has a little drop here and there but not like before. FWIW I have carbon and gfo in 2 separate media bags at the bottom of the cup. Then on amazon I bought a sheet of 2" media sponge and a sheet of filter pad. I used an old filter sock to outline the sponge and filter pad to make cutouts to drop them in the cup. Make the sponge a little bigger than the cup and it will fit snuggly and not float to the top. At first I had a 2" foam on top of the carbon and gfo, 1 layer of filter pad (about 3/4 to 1 in thick) and then another 2" foam on top. That was too thick and too restrictive. So I sliced one of the foam pieces in half (thickness wise) so it was only 1" and all is good. So you can buy 1" foam and be good.