I have two Hydro-Sponge V Filters in my 55gal discus tank run by a whisper 100, Ive noticed that everytime i wash the filters out to get the debris out (which is at the same time i do a w/c) that when i restart the pump that the filters float for a while...most of the time I have to end up squeezing them a few times and hope that they stay on the bottom then. Ive tried doing this prior to starting the pump, but they still float. Its a bare bottom tank so I can bury the weight in the substrate to keep it down...anybody have any tricks or ideas to keep the sponges down?