fishing line works well... if you drill a small hole or three along the lip and slit the sponge so it fits over the lip you can "sew" the sponge on... PM badreverend and ask him for a pic of his betta/guppy tank.. or ill try to get you a pic of his setup this afternoon... ive got a birthday party going on for the kid today but im going to skip out for a bit because im a crappy person
i've got an AC110 on my 55gal, and its not loud at all. just kinda hums very quitely. however, when your water starts getting low, the waterfall is tremendously annoying, as the filter moves quite a bit of water. one tip tho, ditch the lid to the filter as its not needed and just rattles.
I just picked one up at the LFS and put it on my 100G tank in the den. I'm surprised by how quiet it is. Even the waterfall isn't so loud (because of how wide it is I think).
I can hear it a little bit, but it's not bad at all. I don't know if I could sleep with that filter in my room though, but putting it in a fish room outside, it seems pretty quiet to me.
Like most others are saying, raising the water levels does help with the waterfall sounds, but I find that I have to play with them too often as the lid starts to rattle, or the impellers starts to make noises. THe worst is when it wakes you up in the middle of the night and you have to fix it. I have a 140 gallon about 3 feet from by bed so I know from experience that they can cause a loss of sleep. Don't get me wrong, they are quiet most of the time, but they can get to be really loud. I also have a rena xp3 and it is very quiet. My fx5 gets here on monday so hopefully it's as quiet as I heard it is.
