So recently my husband purchased a new sump aquarium for me - I used to have canister aqu previously. They installed it while I was not present and I am left with a pump and electronic metre without any instructions. Aquarium is 400 litres and it is set at 1:12 but the pump blows a huge crater in the substrate and if I move the direction of it, it blows the substrate and fish in the opposite direction. There are no instructions for the set up so how do I turn it down to avoid wiping out my planted tank? The electronic metre has F + - and W on it but no other indicators on how to set it? I was told to remove the pipe inlet and just let the water flow from the top from supplier but this results in the entire rear substrate along with plants being blown to the front leaving just the glass. Then I was told to cut the pipe in half and face it toward the side of the glass which results in a crater of about 6 inches around and substrate blown to the front in a steady pile. Fish are also pushed across - which I am sure is not meant to happen. How do I turn this down without stopping the volume of water going through the correct cycle of the sump?