Well there are many kinds. For a tank that big I would go with a Canister and then a hang on filter.
You can find cheaper ones on
http://www.bigalsonline.com this is the cheaper place than your pet stores. You want your tank to cycle at least 8 times an hour so look at the GPH add the two filters GPH and then take the GPH and divide the tank size into that this will tell you how much your tank will cycle per hour