Hi there. So after some excellent advice from the likes of crispin, tobes, sandlewood, monti and marco , I am planning to build a remote DSB and ATS. Here is the plan, for scrutiny by the gurus I Plan to pump water from the sump to the DSB, collect the drain water from the DSB and let it run onto the ATS. From the ATS directly back to the sump for pumping to the DT. Would it be better to run from the ATS directly to the DT? The DSB: I Plan to use a 1200lph pump to pump water from the sump (after the compartment with the skimmer) to the DSB. The DSB itself I have a medium size black plastic storage box with thick walls and fitted lid. I am going from 15mm outlet from the pump to 50mm PVC piping to reduce the presure and create a softer flow into the DSB. The sand bed I plan for will be about 35cm deep in a 40cm by 50 cm container. This will leave about 25cm clear above the sand. The inflow will be a 50mm Spreader pipe in a T shape. The outflow will be a 110mm to 50mm conversion pipe leading to a 50mm drainpipe for the outflow. I am not planning any illumination in the DSB. The ATS: This is where I will need the most help. I am planning to try and use a smaller tank, about 50x30x30cm. I will run a piece of 80% shadecloth at an angle (about 25 deg so as not too steep) in the tank. I plan to have the outflow from the DBS as the inflow for the ATS, Let the water run down the shadecloth and then drain out of the tank and back to the sump. I am hoping the water will flow through the shadecloth and hence the algae. I am planning on 2 100W powersaver lamps for lighting. Here is a diagram of the planned ATS.