As so often, some companies are just not known for no reason on the market. Price and achievement are correct. The pump is quiet and for Nano super.Beim filter material it might even be an advancement, or to be concerned filter sponge and cut themselves, is also cheaper in the long run. I only had the small version in the 30 l basin, down there was often what lie - with the XL, the soil is clean cleaned of suspended solids.