Well I think it is installed correctly. The black body in/out ports on the bottom stay connected to the pex hoses and the clear top(which is removable) can be seen through for debris as well as more easily removed for cleaning. I am pretty sure there should also be an arrow on the side of the filter showing the direction of water flow (from fresh tank towards pump). If it is installed backwards then it should be flipped around (probably provides more surface area for debris to collect on before the water flow stops). Less critical then the direction of an anti backflow valve, but important.
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