while I do prefer the AC filters for HOB there are a lot of alternative filters you can use now that do a good job and are less pricey.
many of the old whisper style filters now use different cartridges similar to those used in the penguin and emperor filters. so you can have bio media with no carbon. and you can use filter mats in them as they use clam shells that are reusable.
I am toying with the idea of one of these
http://www.drsfostersmith.com/product/prod_display.cfm?c=3578+3579+16729&pcatid=16729
since we have seen some issues with stuff floating on the surface.
again.. research your choices.
in many cases you will be fine.
many of the old whisper style filters now use different cartridges similar to those used in the penguin and emperor filters. so you can have bio media with no carbon. and you can use filter mats in them as they use clam shells that are reusable.
I am toying with the idea of one of these
http://www.drsfostersmith.com/product/prod_display.cfm?c=3578+3579+16729&pcatid=16729
since we have seen some issues with stuff floating on the surface.
again.. research your choices.
in many cases you will be fine.