>The suction cup thing is vaguely annoying. Actually, I don't use the >Tetra sponges much either. I much prefer the Hydros. I didn't like the >dirt magnet because it was much harder to take out of the tank & clean, >and when it was IN the tank, it tended to drift around the tank. We also quit using the Tetra billies because of the suction cups. The sponges themselves are great for placing in tanks that are already going and letting them build up the bacteria and using them for starting other tanks. I just drop them in other tanks. We have also switched all our tanks over to the Hydro-Sponges. >It really is different strokes for different folks with this stuff... Exactly. Kaycy