Aqua-Flo by Gecko Alliance XP2 Pump Impeller Closed face impeller made for the XP2 spa pump by Aqua-Flo by Gecko Alliance. Rated at 1.5hp, it is used in a XP2 wet end, and must be installed on a 1.5hp (or greater) thru bolt motor. Shaft seal sold separately In 2012, the manufacturer changed the way Aquaflo pumps are rated. These pumps are now assigned both an operational horsepower (ohp), and a total horsepower (thp) rating. Previous versions of these pumps used only the operational horsepower. If you are replacing an older Aquaflo pump, be sure to match the operational hp rating rather than the total hp.