pond filter

I just finished installing a 91 gal preformed pond.. I have a small fountain in now, as well as 4 goldfish. My ? is-- do i need a filter? What kind of filter? Any help will be much appreciated. Thanks--- Liz

Liz, Congratulations on your new little pond. Does your fountain have a filter unit in the submersible part?
If not this type of filter would work for your little pond and it has a fountain built in. It would not have to be run all day to keep it clean as this unit will handle up to 1000 gal./per hour.

http://www.drsfostersmith.com/product/prod_display.cfm?c=5163+5186+12218&pcatid=12218