How do I match a cleaner to my pool size and type?

Check the manufacturer's maximum length or square-footage rating and confirm above-ground versus in-ground compatibility before buying. Several Dolphin models are tuned specifically for one or the other (the Nautilus AG for above-ground, various CC trims for in-ground up to 33 or 50 ft). Picking a unit rated below your pool's size is the most common mismatch buyers report.