I just purchased a aquatop cf500 uv and was wondering if any one has ever used one of the these? The claim is that the output is 525gph. It has a 9 volt uv light and also has a spray bary attatchment. It also has 4 media trays. Most of the reviews that I have read have been decent. My intention is to place this on my 55 gallon mbuna tank. it comes with filter pads but no media. I am going to use fluval pre filter which i use in my fx5, bio balls, and fluval ceramic bio pellets. I currently only have a penguine 350 and 150 hob which are have a hard time keeping up. My intention is to hung up the new filter and leave both hob on till the canister filter is cycled. Any thoughs?