Location of RWT inlet and outlet

It is best not to have water falling into the tank from a position where it would stir up the sediment layer near the outlet that supplies the pump if the tank's water level is low.

It is also best to have the inlet basket mesh within arm's reach of the overflow pipe so that the overflow outlet's mesh can cleaned. The mesh however can be removed if the vertical overflow pipe is fitted with an Air Gap that has easily removable mesh for servicing. Removing the mesh from the outlet also increases the overflow outlet's discharge capacity.

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Water settles in stratified layers with the highest density, lowest oxygen layers found at the bottom in the anaerobic zone. Make sure that the outlet that supplies the pump is 100mm above the bottom of the tank at the valve's lowest point. Best practice will have a floating intake filter fitted that draws the best quality water from 200-300mm below the water surface. If one is fitted, then the outlet valve can be fitted at the bottom of the tank.

It is also best practice to connect a flexible UV stabilised hose between the tank's outlet and the pump but use a nut and tail at the tank so that the hose can be easily removed if ever needed.

Also have a straight length of suction hose that respects a minimum 8 internal diameters connected to the pump's suction port.

Also be wary of using Blue Stripe poly pipe because its nominal diameter is measured as an external diameter.