water filter accessories

I'm looking to convert a tank of fresh water in my saltwater tank … Help?

I have a hexagon-shaped 30-gallon tank and a 20 gallon long. Both have all the equipment and accessories made for freshwater settings. But with my "stimulus payment" I want to convert one in a reef system of salt water. I'm doing very well with my freshwater fish, saltwater but whole new world for me. Can someone show me an informative site help me through the transition? My biggest question right now is what type of filter and I need to buy new accessories? Any help would be great!

I looked quickly and found this site: http://www.ehow.com/how_5796_set-saltwater-aquarium.html Good luck!

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