Penguin is similar to Emperor. I have adapted two dif products to make them work in my Emperor 400. There aree equivalent products for the Penguins.
I use the drsfostersmith.com clamshell frames from these:
http://www.fosterandsmithaquatics.com/product/prod_display.cfm?c=3578+4136+13370&pcatid=13370&r=7
With the carbonless pads from kensfish.com (You have to trim a bit of the plastic on the sides ofso they fit the frame.):
[FONT=Helvetica, Arial, sans-serif]KENS CARBON FREE FILTER CARTRIDGES FOR PENGUIN FILTERS:[/FONT]Made to fit Penguin 130, 160, 170, 300, 350 as well as Auto-Flo 1&2, and Ultra-Flo 200, and Aqua-tech 1, 2 & 20-30/30 & 30-60. Carbon Free! (Replaces OEM size C) $1.30 each[FONT=Helvetica, Arial, sans-serif]
[/FONT][FONT=Helvetica, Arial, sans-serif]
[/FONT]http://www.kensfish.com/kensfilterinserts.html
I clean the pads using a 25% bleach solution in a bucket overnight. Rinse em well and let em dry and they can be reused. I keep two sets of frames and 3 sets of pads and am always ready to remove and replace every week that way.
I use the drsfostersmith.com clamshell frames from these:

http://www.fosterandsmithaquatics.com/product/prod_display.cfm?c=3578+4136+13370&pcatid=13370&r=7
With the carbonless pads from kensfish.com (You have to trim a bit of the plastic on the sides ofso they fit the frame.):
[FONT=Helvetica, Arial, sans-serif]KENS CARBON FREE FILTER CARTRIDGES FOR PENGUIN FILTERS:[/FONT]Made to fit Penguin 130, 160, 170, 300, 350 as well as Auto-Flo 1&2, and Ultra-Flo 200, and Aqua-tech 1, 2 & 20-30/30 & 30-60. Carbon Free! (Replaces OEM size C) $1.30 each[FONT=Helvetica, Arial, sans-serif]

[/FONT]http://www.kensfish.com/kensfilterinserts.html
I clean the pads using a 25% bleach solution in a bucket overnight. Rinse em well and let em dry and they can be reused. I keep two sets of frames and 3 sets of pads and am always ready to remove and replace every week that way.