www.fosterandsmithaquatics.com has a good sell on whisper power filters that ends tomorrow. I just bought one and it works really well.
The whisper 40 is on sell for only $16, that would be more than enough for a 20 gallon, or run two 30's with the flow turned down a little for double the filtration, or one 60 with reduced flow.
I just ordered my first whisper filter, it works great so far, the price makes it better. If you get a noisey one, call up tetra and they will ship you parts needed to fix it. (the whisper I just received only has a slight motor hum if my head is right over it)
My aquaclear is nice, but they are really too full of themselves on the price they charge. You can reuse the bio bags, and put any media you want in them. If you get the bio 3 filter kit that website offers, you can make your own filter cartridges with the frames they give you (they also have them for penguin and emperor filters).
The adjustable flow also works better on the Whisper, the aquaclear still has a pretty hefty flow on the lowest setting which is a pain if you feed flake food.. (I have a AQ 70 on a 37 gallon aquarium)
Just thought I'd toss that out there, I have quite a few different HOB filters, they all work (even those new aqueon ones with the dinky bio media frame), it just comes down to how much money you want to fork out. You can use the cartridges until they fall apart as long as you remove the carbon once it expires. I got about 6 months out of a set of Emperor filter cartridges once.
Also remember, with HOB's, get one rated for twice your tank size. If you get one with adjustable flow, you can always slow it down a bit if it's too much for the fish.
Canister filters are nice, but they are harder to clean out (takes me a good 20+ minutes to clean out my 4 stage canister and get it running again, where as the cheaper HOB style you can pull out the cartridge and rinse it off if it looks full. It takes a canister a lot longer to get full, but that just means you leave all that crud in your water that much longer as well.
I have two generic canisters that are only sold on ebay that work great. Check out the "sunsun pimps" page on this forum. Thats the newest popular generic canister (runs about $50-$60 after shipping)
As far as penguin vs emperor goes, penguins are much quieter. They removed the adjustable flow from the emperors, so basically they are just louder penguins with a spray bar over the bio wheels and a media tray, (i believe the new penguins even have room for a optional media tray, but not positive. Even if not, there is still room behind the cartridge for a small media bag.
I'd jump on that whisper sale, you could buy two of those for the cost of one popular filter right now. (3 for the cost of a similar sized aquaclear). I received my order two days after ordering.
Out of the HOBs I have, the quietest is aquaclear (unless the lid decides to randomly rattle), then whisper, then penguin (faint water trickle noise from bio wheel, but not always), then tetratec (with the living filter chamber disabled), then aqueon quietflow (trickle noise and impeller hum), then emperors (trickle noise and slight motor hum and some times lid vibrations).
Also, the new emperors, penguins, and aqueon filters don't have the flow control. Aqueon filters have short intake tubes and the least versitile cartridges out of the lot, but are the easiest to use.
If you go with a aquaclear, buy a uncut blue bonded filter pad
http://www.fosterandsmithaquatics.com/product/prod_display.cfm?c=3578+4136+4231&pcatid=4231 to put on top of the sponge (once you cut it to the size of your sponge, i sandwich mine between two sponges then top it off with biomax). They are good filters, but don't grab the smaller particles with the sponges alone. Those pads are more reusable than the poly fill stuff we use for water polishing. I've just replaced the first one i cut out after about 7 months of use. And with using the two sponges you can just rinse the first sponge and blue pad in the sink if you arent doing a water change, you still have the second sponge and bio max for the bacteria, not to mention the whole rest of your tank.
ok, playing on forums when I'm bored is a bad thing, I'll stop typing now. :icon_mrgr
Good luck with your new setup.
