Patriot Turtle HydroFlow 2100 GPH Submersible In Pond Pump Extremely energy efficient magnetic drive technology is an ideal choice for fountains, waterfalls and most ponds. Intake screen prevents clogging while passing solids up to .25 inch. Weve tested these units with over 50% intake blockage with no reduction in flow! Asynchronous drive motor can be controlled with variable speed controller (not included) that permits you to increase or decrease pump flow as needed. Contains no oil; completely safe for fish, wildlife and aquatic plants 2-year manufacturers warranty: The speed controller does NOT work with the AP10000 and AP12502