Hi guys. But of a newby to this. Does anyone know how the water flows through the ,Velda clear control100 filter. It has 3 compartments plus a sump with both the inlet and outlet at the top. One on the right is for the uv units if fitted and throne on the left is for additional filter material. Just don't know if that one on the left fills from the top or bottom. Cannot find anything on the Velda website. Any help would be appreciated