Posted: Thu Sep 22, 2011 7:44 pm Re: Fluval FX5
17" is just to the top of the canister, you need some clearance above for the hose connections as well, but that is covered in the manual ElectricTurtle linked.
5 inch RES male named Jordtim
Hardware: 75 gallon tank (21"H X 48"W X 18"D), FX5 filter with veipacray media setup, pool filter sand substrat, TurtleSafe halogen heat/UVA lamp and ReptiGlo 5.0 UVB lamp in ZooMed Dual Dome Fixture.