Fluval Fx4 Externer Filter 2650 L / H.

Excelente producto calidad precio tiene una capacidad de filtraje muy buena

I have this filter for my 720L tank, it's great though I recomend to clean it more often if you have goldfish than other aquarium fish as they give off more waste than other more excotic fish. you can tweak the flow on both the in and outlet aswell as a smaller drain beside the electrical part of the filter (where you can empty out waste before cleaning or to ease the filter for further work.