Left: 24 inches Right: 18 inches You will need an additional 4 1/2 inches height to remove collection cup. Both are ran by a Hagen 802 powerhead (an upgrade pump can be used if you are a good DIY) I am asking $100.00 for the 24' and $75.00 for the 18' Thanks for looking/DesktopModules/ActiveForums/themes/_default/emoticons/biggrin.gif