Eheim Professionel 4 Plus is the latest product in ever popular Professionel series. Equipped with an ’emergency’ button to prolong service intervals. Great filter, very easy to put together and clean. In fact, I only clean mine every 4-6 weeks or so and my water is always crystal clear. Very powerful, the pump power is around 950 litres per hour which is more then enough for my 96 litres aquarium. Power consumption is very low, only 12 watts. The filter volume is about 3.5 litres. Great quality product, you can’t go wrong really.