Well, I used to swear by my dual 30-60 whisper filters on my 55 gallon, but lately they were clogging so much I'd have to clean the filter pads twice a week. Finally broke down and bought a new pack of pads. You can't beat the price for whisper filter "bags", 8 for like 10 dollars at wal mart. You also get bags of carton you can choose to use.
I believe keeping a whisper good and running is to replace the "bag" cartridges once every 2 months or as needed. I usually scrub them down in tank water, but it gets to a saturation point and they just turn black and nasty. And thanks to the "biofoam" grid in each outtake flow, that holds in the bacteria. I've found changing all four bags at once does not affect the bacteria.
I'm also running each bag empty as opposed to packing it with peat. They get nasty fast that way.
My tank is still a lovely red tea color too.
And on a completely different note, I really need to get off my *** and water change the 3 gallon guppy tank. Ever since I discovered a leak at the very top near the plastic brace rim, I've dreaded the 50% water change-out/investigation I'm going to have to do. Plus it's an Eclipse and acryllic, which aren't supposed to crack.
I believe keeping a whisper good and running is to replace the "bag" cartridges once every 2 months or as needed. I usually scrub them down in tank water, but it gets to a saturation point and they just turn black and nasty. And thanks to the "biofoam" grid in each outtake flow, that holds in the bacteria. I've found changing all four bags at once does not affect the bacteria.
I'm also running each bag empty as opposed to packing it with peat. They get nasty fast that way.
My tank is still a lovely red tea color too.
And on a completely different note, I really need to get off my *** and water change the 3 gallon guppy tank. Ever since I discovered a leak at the very top near the plastic brace rim, I've dreaded the 50% water change-out/investigation I'm going to have to do. Plus it's an Eclipse and acryllic, which aren't supposed to crack.
Have your tried using the polyester filling that you can get in the craft section? I used to use the regular filling, but the stuff on the rolls is MUCH easier to work with and still lasts for a very long time. I bought the $6 roll about 4 months ago, changed out the mechanical media in 2 canisters twice, and 4 HOB's and still have a ton of the stuff left. You can cut it to any size you want, and add as much as you want to increace the effecency of the pads. Well worth the extra time it takes to cut it out. 
