Review on SumpMarine Water Transfer Pump, 115V - Efficient 330 GPH Portable Electric Utility Pump with 6' Water Hose Kit - Perfect Solution for Removing Water From Gardens, Hot Tubs, Rain Barrels, Pools, Ponds, Aquariums, and More! by Cho Screeton

Functions as described (although I can't say I measured the performance but it seemed high). So why 3 stars? 1. There is no on/off switch - it must be unplugged to turn off.2. contradicting directions. The leaflet says you turn it on and it works, but there was a sticker on the pump itself to fill it with water before starting.3. incomprehensible direction. Do I only smear it the first time? Any use? Sometimes?4. No automatic shut-off in case of lack of water. That means I have to be careful when emptying the hot tub or I'll burn it. On the loud side