HEY ALL.....
YES, I USE THAT ONE....WITHOUT IT, IT WOULD SOUND
TOO LOUD AND CAUSE BUBBLES TO RETURN TO THE
DISPLAY TANK...IF THERE WAS SOMETHING ELSE TO
REPLACE IT WITH THAT WOULD WORK JUST AS GOOD,
I WOULD GET IT CAUSE THAT SPONGE IS ALSO A
NITRATE MAGNET....
YOU KNOW THAT THE SKIMMER SPONGE...