Hi, I have the old Oceanic overflows which were loud when I first got my tank. The owner of my local fish store just said to fill the overflows full of bioballs to muffle the sound.....which I did. Then I saw the micronfiltration sheets or rags, they call them pads, and decided to scruntch them up on top of the bioballs in the overflows the water flows both through and over the top of the scruntched up filter rags. They work perfectly and they come in big sheets and you can cut them any size you like. Every week or two I take them out and put them in the washing machine with a cup of fragrance free bleach (no soap), on small to med. load size and they come out snow white. I then soak them for a few minutes in a pitcher of fresh water with some chlorine/chloramine remover for fish water. I only replace them once a year or so. Works great and the tiny particals are removed before too much reaches the sump. Now I have a wet dry filter in my overflow and one could even do this and not need much in the way of a wet dry below....maybe use it for a fudge?